also check your fuel pressure and remove the injectors and clean them out the best you can with some brake cleaner. it looks like you was running rich on 2 3 and 6. a lean condition will cause a misfire and will superheat the catalytic converter. what spark plugs did you use?
Beat the Dead Horse. Overheating XJ
- Thread starter a_kelley
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a_kelley
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its the plugs it had when I got it, new looking Champion RC12LYC.. I think my MAP sensor line has a leak, but that wouldn't explain only half the cylinders rich.. It did when I messed with it, change the misfire at idle... could help fuel economy too probably.. I was going to put some quad-port Dodge 2.0L SOHC injectors in it, when I got time.. I hear it atomizes the fuel better.. we shall find out at some point.. I was pondering why those valves/chamber tops looked black.. I thought running rich made the cat heat up? Because then its forced to burn the extra fuel..
when the computer thinks the motor is runnign lean it will try and compensate by dumping more fuel in. also with the motor running lean the motor will hesitate. and any normal driver will like to press the gas pedal harder to try and push the motor to the desired speed. if your CE light isnt flashing then the misfire isnt that bad. it is probably from the motor/fuel lines getting too hot and vaporizing the fuel. i would try the exhaust tomorrow and see what happens. doesnt cost anything and its a simple test.the injectors are easy to clean too. i had a buddy whose fuel pump started failing and he dogged the crap out of it until i got the new pump in. it was misfiring so bad sparks were shooting out the tailpipe. thats with 24 psi at the rail. so yes your technically running rich but the computer thinks lean. or thats my experience and thats the best way i can explain it haha
a_kelley
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I measured the cat conv after going down the road and its no hotter than the pipe before it or after it.. dunno if that means anything. I'm going to pickup another sensor and gasket and put my other thermo housing that I drilled and tapped on it.. then my gauge should read properly, its drilled into the heater side of the housing, so if the thermostat sticks the gauge will still read correctly..
what about the radiator cap? what pressure rating do you have? if i remember right its supposed to be 16 lbs. if anything higher then it will allow the pressure to raise and higher temps. if its hitting 250 then it should be spewing out of the reserve tank. mine did that only at 220
a_kelley
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I told the guy at the parts store I need a radiator and cap, so I assume he looked it up.. Its a 13lb cap, seemed low to me, but would just make the boil point lower... I know it is NOT hitting 250.. I put a infrared thermometer on the thermo outlet neck and it was 220 +/- 5 degrees (tolerance on the thermometer, seeming to me to be 215, fan wasn't on, and it is supposed to come on at 220) The cat was replaced at some point. BTW my other motor did the same thing with the same sensor, same gauge, same harness, different jeep. Never has boiled over with the cap on. I did figure out the air in the hose was from the overflow tank, I think its plugged in the uprise tube, I took my tube off and shoved it down in the tank itself and the air came out of the upper rad hose.. SO I'm going to put a new sensor in my modified thermo outlet.. If I could remove my old sensor, I would test it, since I got a meter, BUT the valve cover is in the way of removing it (with socket or box end), and open end wrenches flare out trying to remove it.... so I'm just relocating it to the water outlet, since in '96 they killed the sensor on the back of the head.. I think due to erroneous readings biased by the exhaust passage only 1/8" under the end of the sensor (and going to OBDII computerized gauges) It may just be the sensor, but I won't worry with it.. I ran it all day today, about 3-4 hrs of driving and it never moved over 250 (on the dash gauge, which at 250, the outlet is 210-215)
ty20404
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Sorry to hijack but I'm having a very similar problem with my new XJ. It's a 4.6L Stroker and I've got all new hoses, 180* Stat, waterpump, and sender (with white plug). It's getting hot, the gauge reads 190ish when moving, but when I stop it begins to creep up. Even past 220* the aux fan is not coming on and I'm getting very frustrated as to why its getting so hot. I tested the fan by pulling the plug on the PCM temperature sensor which promptly turned the fan on... So the relay and fuses work, but does this mean that my coolant really isn't as hot as my gauge is saying?
Should I wire a switch into the aux fan? Get a bigger radiator?
Should I wire a switch into the aux fan? Get a bigger radiator?
a_kelley
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How old is your rad+cap?
180* thermostat will only take it longer to heat up, it won't change max temperature. Measure your CTS on the thermo outlet with an ohm meter. what year XJ?
For a '94 (pulled from something I found on the internet somewhere (pm if you need to know or want it and I'll find the link))
I put in my alternate water outlet on with the sender in it and the gauge was still wrong. Infrared thermometer says 205 - 215 and gauge says 240. I ended up looking up resistance spec'd for the sender and its supposed to be 93.5 ohms at 220*... mine read 158 or so with the inframometer show 210. my dash gauge is wrong for the sender (reads high) I just boiled a sensor from a 84-91/92? and it read 158 @ 212.. So I think my gauge is broken... I'm swapping in the old sensor (post type) and the old cluster and see if it changes. I have two sensors, one in the back of the head and one on the water outlet, both read the same, 158, running idle for a good bit (operating temp).. should be about 210, unless aluminum is really that slow at conducting heat (almost as good as copper/brass) but my fingers tell me its not slow. I'll post up later on. Check and make sure your gauge is accurate!
a_kelley
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Well, I changed out the connector for the sender and the sender to a 91 or 88, can't remember but they are the same, and Thank God, the gauge is right! (I didn't change the gauge, it was in a '93 cluster) I thought the sender was one with the white connector, but that was wrong.. I thought I was sure as sure that it was but that was wrong. AZ even lists the white connector sender for a '93, but mine was a 91 type with the screw thread and shove on connector.. WTF JEEP?! Been chasing this since I put my previous jeep together, and didn't figure it out until today... Weird is all I know to say.
And I left the sender in the thermostat housing... I can't remove the one on the back of the head until I remove the valve cover.. the 91 sensor is 13mm and the 93/94 sensor is 14mm, which doesn't allow the box wrench/socket to fit down on it because of interference
And I left the sender in the thermostat housing... I can't remove the one on the back of the head until I remove the valve cover.. the 91 sensor is 13mm and the 93/94 sensor is 14mm, which doesn't allow the box wrench/socket to fit down on it because of interference
ty20404
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Its a 1996 classic. I really hope I'm having the same problem with the gauge/sender because that would explain why the gauge is high and the fan isn't coming on. I have the white plug on my sender (13mm)... I'm confused as to what you're saying which one is correct and I know we have different years, but do you know which one I need?
I don't have a voltmeter/ohmmeter but I will try and find one and check it. Send me the link for that site, hopefully there is a chart for the 96.
However, the issue with the fan is that it doesn't even come on when the A/C is turned on but I know that it works because when I pulled the plug from the temp SENSOR it kicked on. Anyone know why it won't come on with the A/C?
The only thing that makes me think my sender is alright is that when moving the gauge reads about 200/205... That is with a 180 degree t-stat, so I guess it could be reading high... Any help is greatly appreciated because I don't want to cook this stroker.
I don't have a voltmeter/ohmmeter but I will try and find one and check it. Send me the link for that site, hopefully there is a chart for the 96.
However, the issue with the fan is that it doesn't even come on when the A/C is turned on but I know that it works because when I pulled the plug from the temp SENSOR it kicked on. Anyone know why it won't come on with the A/C?
The only thing that makes me think my sender is alright is that when moving the gauge reads about 200/205... That is with a 180 degree t-stat, so I guess it could be reading high... Any help is greatly appreciated because I don't want to cook this stroker.
a_kelley
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200-205 would be right for a 180 tstat going down the road.. at idle sitting, it will go up.. The sender you have ought to be the correct one. Mine was the wrong sender because I had interchanged harnesses between a 93/94 and maybe someone swapped the gauges along the way. If the fan isn't kicking on your temp sensor may be faulty, but that doesn't explain why it doesn't come on with the AC. Does it come on when MAX AC is on? it ought to then since it forces the AC compressor to run all out until it hits the pressure limit. If not, uhhh I don't know what to tell you.. Jody might pipe in if he's still watching this thread..
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This has been a very informative thread. Gonna bookmark this as I'm sure I'll be seeing temperature troubles as summer approaches.
ty20404
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I'm getting 158 ohms for the temp sender when my gauge says 210*, and I'm getting 828 ohms for the temp sensor when the gauge was about 200. According to what you're saying for both the sender and the chart for the sensor everything appears to be correct for me... If I'm reading correctly.
Looks like I need to move onto the radiator? Water pump? Maybe there's STILL air in there... Don't know how because I've bled it multiple ways 5 million times or so...
Looks like I need to move onto the radiator? Water pump? Maybe there's STILL air in there... Don't know how because I've bled it multiple ways 5 million times or so...
a_kelley
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The sensor is good, according to your measurements. if you are not running over 210-215, that's considered normal operating temperature.. anything over 215-220 is cause to start looking at things. if you run under 195, it will be operating "open loop" and you will lose power/fuel mileage. the fan is supposed to kick on at 217 I believe. I ran across a mod to alter the sensor's resistance to make the fan kick on sooner... I believe it was a 4k resistor in parrallel with the sensor wires in the harness. And you can put a switch in there if you get running like crap in the winter..
Here's the link http://www.angelfire.com/my/fan/CTS.html
(other cool stuff at http://www.angelfire.com/my/fan/ )
how cruddy was the antifreeze that came out of the radiator before you put the stroker in? If it was cruddy or current antifreeze is cruddy, try reverse flushing the radiator. If it doesn't look discolored, don't worry about that.
if you think the pump is the cause, you can try and squeeze/kink the heater hose coming from the head and see if you can feel the pressure build on it.. you should kinda feel a little pressure build up, at least I could with a 6 month old pump.. of course you can always pull the hose and have an assistant crank and shut off the motor 1 second after it starts and you should be greeted with a small fountain out of the upper heater hose outlet (tip from Jody).
To check thermostats, suspend in a pan of water on the stove (please use stainless and wash it well or buy a cheap one from the dollar store) put a thermometer in there. you should see the thermostat begin to open when it hits the temperature on the thermostat.
did you check the fan coming on with max ac?
shake the upper hose, you'll hear water sloshing in it if there is... and if there is check to see if the overflow hose is stopped up, or the bottle tube.. I ended up sticking my hose down in the tank and that worked.. dunno why it wasn't pull through the bottle tube..
ty20404
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Originally the coolant was okay and not too bad. The system had been overheated by the previous owner (resulted in a cracked head) which prompted me to buy a stroker
Since the install I have drained it (and everything looked quite clean) filled with a half gallon of vinegar, the rest water, ran to temp then drained. I pulled the radiator out and plugged a hose up to all three openings while moving the thing around to get water to pass through all of the fins. Nothing drastic came out of it and the water passing thru was clear and there didn't seem to be any blockage.I feel as though with the added heat of the stroker that the stock radiator is just barely not efficient enough to keep her cool while sitting. I think my problem will be solved with a 3 core aluminum radiator and maybe a flowkooler high flow pump.
The thermostat is a Gates product so I'm pretty trusting in that it works fine. Like I said, cruising around she sits right about 200-205. Stopped it slowly creeps up. I've sat for 20+ minutes before and it hasn't even made it all the way to the tickmark preceding the danger zone. Of course, I could just still have air in the system that makes its way to the top of the head when idling. I swear I've burped it 4 times now, but will try again tomorrow.
Max A/C wont kick on the fan for some reason. I did some diagnostics on the relay and the relay plugs. When I jump from the power supply for the relay to ground I should be reading 12V correct? I don't think that I'm getting power to it. I know for a fact that the fan works because I jumped it according to lunghd's A/C diagnostics and it kicks right on.
It also doesn't appear to be coming on at 217 either. I pulled literally every fuse there is and checked them and none were popped. Does anyone know where else to look for this stuff?
One thing I have noticed, which may or may not matter, is that my interior fan/blower only works in the High position. Nothing happens anywhere else. I think I did see that the blower had been replaced with a Uni something branded item.
My next step will be to let her get hot, say about 220 to 230 then check the resistance on the temp sensor and see if that is reading the corresponding resistance for 220/230 or if it's still 210ish. If it's still 210ish then it has to just be air making its way to the sender.
a_kelley
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Originally the coolant was okay and not too bad. The system had been overheated by the previous owner (resulted in a cracked head) which prompted me to buy a stroker
I feel as though with the added heat of the stroker that the stock radiator is just barely not efficient enough to keep her cool while sitting. I think my problem will be solved with a 3 core aluminum radiator and maybe a flowkooler high flow pump.
The thermostat is a Gates product so I'm pretty trusting in that it works fine. Like I said, cruising around she sits right about 200-205. Stopped it slowly creeps up. I've sat for 20+ minutes before and it hasn't even made it all the way to the tickmark preceding the danger zone. Of course, I could just still have air in the system that makes its way to the top of the head when idling. I swear I've burped it 4 times now, but will try again tomorrow.
Max A/C wont kick on the fan for some reason. I did some diagnostics on the relay and the relay plugs. When I jump from the power supply for the relay to ground I should be reading 12V correct? I don't think that I'm getting power to it. I know for a fact that the fan works because I jumped it according to lunghd's A/C diagnostics and it kicks right on.
It also doesn't appear to be coming on at 217 either. I pulled literally every fuse there is and checked them and none were popped. Does anyone know where else to look for this stuff?
One thing I have noticed, which may or may not matter, is that my interior fan/blower only works in the High position. Nothing happens anywhere else. I think I did see that the blower had been replaced with a Uni something branded item.
My next step will be to let her get hot, say about 220 to 230 then check the resistance on the temp sensor and see if that is reading the corresponding resistance for 220/230 or if it's still 210ish. If it's still 210ish then it has to just be air making its way to the sender.
Try letting it run with the cap off... you may find that when it gets up to thermostat temp (180-190ish) it will bubble up some air.. you may have to give it a little throttle -- but be careful it will boil out if you feed it enough throttle, long enough.. but just throw the cap on before you let off the throttle and it won't boil out..
Shouldn't matter about the blower, but uh, thats either your blower resistor or the blower switch.. try this on the fan relay -- pull it, flip it over you will see two 'tabs' that are part of the plastic cover on the relay.. take a suitable device (pocket knife works for me), screwdriver, and gently pry the tabs up off the locks.. if you look at it when you've got the cover off there is a hinged piece of metal, thats your common on the output of the relay. if you reinstall it and push on it, you can verify that the output side of the relay has power, and that the fan works from the relay output..
when you remove the relay, hook the voltmeter to ground, turn on ignition, you should have power on two terminals on the fan relay location. one is power for the fan, one is power for the relay. If you've got both, you can use a wire to jumper the ground side of the relay coil to the ground side of the ASD relay coil and the fan will magically run whenever you turn the key on, if thats something you'd like to try..
ty20404
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I did that to verify that the fan would work. But that's also because I used the constant switced voltage jumped to the fan output. I think that I'm not getting input to the relay to tell the fan to turn on. I will check this again tonight.
Even still, its only been about 80 outside and once it gets to be 100 I don't think the aux fan will be of that much help to keep her cool while crawling.
I will also check the resitance on the sensor to see if it corresponds to a hot motor (when the gauge is reading 220+). If the resistance on that corresponds to 220 or below when the gauge reads higher that must mean air pockets near the sender.
Which way does the water flow through the radiator? Does the pump push into the radiator or out of the radiator? I will check that I'm getting the right pressure buildup by squeezing the radiator inlet tube also. With a new Gates pump though it should be okay. If the sensor is reading resistance that corresponds to the gauge temp then it is time to order a new 3 core aluminum radiator.
Of course I still need to troubleshoot what's wrong with my fan to figure out why its not turning on with the A/C or high temps. It may not be turning on with the A/C because the system isn't charged, so the compressor isn't cycling... An explanation for that... If the sensor isn't reading high that would also explain why it doesn't come on when the gauge reads 220+. If it does read corresponding to the gauge then obviously there's something wrong with the switching mechanism for the fan between the PCM and the relay.
I know lunghd's tutorial states that there is a diode module near the driver's side fender for the fan but that was for Renix models and I don't see anything in that vicinity that represents a "module" of any sort unless it is inside that box next to the intake. Anyone have any insight into this diode issue? Maybe a diagram for 96ish aux fan wiring?
Even still, its only been about 80 outside and once it gets to be 100 I don't think the aux fan will be of that much help to keep her cool while crawling.
I will also check the resitance on the sensor to see if it corresponds to a hot motor (when the gauge is reading 220+). If the resistance on that corresponds to 220 or below when the gauge reads higher that must mean air pockets near the sender.
Which way does the water flow through the radiator? Does the pump push into the radiator or out of the radiator? I will check that I'm getting the right pressure buildup by squeezing the radiator inlet tube also. With a new Gates pump though it should be okay. If the sensor is reading resistance that corresponds to the gauge temp then it is time to order a new 3 core aluminum radiator.
Of course I still need to troubleshoot what's wrong with my fan to figure out why its not turning on with the A/C or high temps. It may not be turning on with the A/C because the system isn't charged, so the compressor isn't cycling... An explanation for that... If the sensor isn't reading high that would also explain why it doesn't come on when the gauge reads 220+. If it does read corresponding to the gauge then obviously there's something wrong with the switching mechanism for the fan between the PCM and the relay.
I know lunghd's tutorial states that there is a diode module near the driver's side fender for the fan but that was for Renix models and I don't see anything in that vicinity that represents a "module" of any sort unless it is inside that box next to the intake. Anyone have any insight into this diode issue? Maybe a diagram for 96ish aux fan wiring?
a_kelley
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Water flows from upper hose to lower hose in the radiator. Pump pulls water from the radiator/pushes into block/up thru head/out the water outlet on the front. Lower radiator hose should not be able to be squeezed (spring in it or should be, if there isn't that hose can suck flat at high RPM but it seems like thats fine since going down the road is fine) The upper radiator hose is the high point in the system, so any air will get trapped there and you ought be able to take it and shake it to see if there is air in it..
Correct.. you have power to the coil on the relay? so in other words if you ground the ground side of the coil, the fan will run?
There is no diode module on a 96. It was used 84-90 to tie the A/C switch for the fan with the temp switch in the radiator. I'll take a look in a minute for the fan diagram. well .. http://www.greatlakesxj.com/tech.html .. he's got 95 and 97, i'd say look at the 97 diagrams
ty20404
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Uhhh, the empty plug that has been hanging just under the power distribution center is plug C143.... That would be the A/C low pressure switch.
Would explain why the fan doesn't come on when the A/C is turned on. I have no idea what would have happened to it. I would recall having taken it out if I did when I pulled the motor. The PO must have removed it.
Shit.
Edit: Does my system need both a high and low switch? Or is there only one binary switch needed? I can't find a "low" side switch anywhere online? Just high side.... If that's so, why is there a connector for the low side switch?
Would explain why the fan doesn't come on when the A/C is turned on. I have no idea what would have happened to it. I would recall having taken it out if I did when I pulled the motor. The PO must have removed it.
Shit.
Edit: Does my system need both a high and low switch? Or is there only one binary switch needed? I can't find a "low" side switch anywhere online? Just high side.... If that's so, why is there a connector for the low side switch?
a_kelley
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Thats a good question.. on my '93 (has both low/high connectors) I had it only hooked up to the high pressure switch? It didn't have a LP switch.. of course it was hooked to a '88 AC system, but all the same.. I never remembered unhooking it from something when I pulled it..
AZ lists two for a '97 but I suspect they are both high pressure switches http://www.autozone.com/autozone/parts/1997-Jeep-Cherokee-4WD/A-C-Switch/_/N-j96h5Z91t6l
Is the compressor and the temp sensor in the heater box hooked up? The compressor should still run even if the system is discharged... It just won't shut off for reaching pressure.. on MAX ac though my '93-94 will run the fan, but not without the HP switch and AC compressor plugged in.. or just chase the Blue/Red wire in the harness to the computer (unless they changed color on 96) and ring it (continuity test) through to the coil ground on the PDC
EDIT: my guess at the LP SW connector's existence is a provision for compressor protection.. only a guess. oh and my temp sensor on the back of the head was reading the same as the thermo housing sensor, so really the location thing I was guessing at about being close to the exhaust port was w.r.o.n.g.
ty20404
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I'm starting to think that there is only one switch for the A/C... Reason being I cannot find any information about a low pressure switch on a 1996, Advance doesn't carry a LP switch, and I can't find one online. I will call the dealership tomorrow to confirm, but it would be nice if someone with a 1996 or later can run outside and look and see if theirs has two switches or just one on the dryer.
I replaced the cap and that didn't do anything really. I did notice on my way to the parts store that at one point the temp jumped up to about 212ish, just passed the mark, then promptly back down to 200ish fairly quickly.
When I got back I let the jeep run until the gauge read about 230ish, just before the 3/4 mark then immediately turned the car off, popped the hood, disconnected the plug to the sensor then checked the resistance. It was reading about 675 then, and after a few minutes got down to about 640 as the engine was still getting a little warmer. According to the chart above that is within the range for 212*...
Judging by this, there's two possible reasons. The first: bad temperature sensor. The second: there's still air, but only just enough that while moving the pump is moving enough water to keep the bubbles away from the temp sender, but while idling the air slowly collects at the sender.
I'm getting really frustrated with this and I guess I'm going to just revv it up without a rad cap on it and and the nose really high and let it spew a bit and hope that it expels all of the air. Then I'll just top it off and go from there.
Addition: Of course, if the sensor is reading properly that would explain why the aux fan isn't kicking on. The fan probably wont come on with the A/C if the compressor isn't cycling due to having no pressure. That is also considering that my Jeep should only have one sensor. I will also add that I turned the ignition on and checked the voltage across the empty plug for the "low pressure" switch and was only getting something like 130mV.
I replaced the cap and that didn't do anything really. I did notice on my way to the parts store that at one point the temp jumped up to about 212ish, just passed the mark, then promptly back down to 200ish fairly quickly.
When I got back I let the jeep run until the gauge read about 230ish, just before the 3/4 mark then immediately turned the car off, popped the hood, disconnected the plug to the sensor then checked the resistance. It was reading about 675 then, and after a few minutes got down to about 640 as the engine was still getting a little warmer. According to the chart above that is within the range for 212*...
Judging by this, there's two possible reasons. The first: bad temperature sensor. The second: there's still air, but only just enough that while moving the pump is moving enough water to keep the bubbles away from the temp sender, but while idling the air slowly collects at the sender.
I'm getting really frustrated with this and I guess I'm going to just revv it up without a rad cap on it and and the nose really high and let it spew a bit and hope that it expels all of the air. Then I'll just top it off and go from there.
Addition: Of course, if the sensor is reading properly that would explain why the aux fan isn't kicking on. The fan probably wont come on with the A/C if the compressor isn't cycling due to having no pressure. That is also considering that my Jeep should only have one sensor. I will also add that I turned the ignition on and checked the voltage across the empty plug for the "low pressure" switch and was only getting something like 130mV.
a_kelley
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def sounds like an air pocket
yep.. sounds about right..
Thats about what I did, but I just let it warm up to idle with the cap off, and when it got close brought it to maybe 1500-2000 and the most of the air came out.. the rest came out after I capped it and it cooled.. is it pulling fluid back from the resevoir? I ended up taking my hose off the resevoir and sticking it down in a bottle of 50/50 AF above the rad cap, and running with the lever vent set to vent to overflow and watched it percolate and pull back.. I did have to squeeze the upper heater hose and the upper rad hose, but they are hot by then.. I could feel air traveling throguh the restriction I created by squeezing it... but it only took about a cup or two of antifreeze out of the container..
EDIT** also just thought you could run compressed air thru the reservoir hose and see if it percolates in the reservoir... it'd also blow crap out of it if there was any.
That's the conclusion I reached with mine.. If your jeep is dirty underneath/near the plug, is it look like its been connected? I don't think they have a LP switch.. HP switches on when pressure is low and off when pressure is high, I imagine...
I think one of the best $30+tax I spent was on that non contact thermometer.. but its not absolutely accurate like a mercury or alcohol thermometer.. tolerance of 2.5% of temp, so for 200*, its a +/- 5* variance.. but close enough for auto cooling applications I suppose.
If you have access to a rad pressure tester, you can pressurize it and if the pressure rolls off quick, then stops and you can repressurize+hold, you have air in it.. alternatively you could take a vacuumable container, put a hose on the bottom of it, fill it 1/2 with antifreeze, connect it to a hookup like a pressure tester has and pull vacuum on the top of the container, and leave it a bit, the level should fall in the container either while pulling vacuum or when you release the vacuum.. being that water/antifreeze is non-compressible, it follows that it also is non-vacuable... air however.. thats my dad's idea, I haven't tried it for lack of an adequate vacuum source.
ty20404
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Okay, it's not the low pressure switch. Somehow I got C143 and C145 mixed up. It is the ambient air temp sensor wire. C145 goes to C409 which plugs into the sensor there.
The thing that's confusing is AZ, Advance and Oreilly list a A/C cutoff High Side... Technically this is the low pressure switch. Get it? If the high side line has the low pressure switch! And the high pressure switch is on the low side... I guess? If it has one?
The thing that's confusing is AZ, Advance and Oreilly list a A/C cutoff High Side... Technically this is the low pressure switch. Get it? If the high side line has the low pressure switch! And the high pressure switch is on the low side... I guess? If it has one?
ty20404
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- Feb 14, 2011
- Location
- Wilmington
Just bled the system again. Took the cap off a cold engine, revved it up to about 2500 for a little while then capped it after a total of about 1 minute running without it. Seemed to have brought the engine operating temp down just a touch. Didn't even creep up at all at stop lights but when I got home I let it sit and it began to creep up again. Let it get to about 235* then shut the car off and immediately tested the resistance on the temp sensor. I got about 614 at the lowest which should correspond to about 218* at the warmest........
I guess I'm just going to continue to bleed it until it finally stops "overheating". Does anyone in the Mooresville or Raleigh areas have an IR Temp Gun? I really want to check the temp on the thermostat housing and cylinder head when the gauge reads 235*. I gotta believe the system is just being a bitch about getting air out.
I guess I'm just going to continue to bleed it until it finally stops "overheating". Does anyone in the Mooresville or Raleigh areas have an IR Temp Gun? I really want to check the temp on the thermostat housing and cylinder head when the gauge reads 235*. I gotta believe the system is just being a bitch about getting air out.
a_kelley
mechanical fixer
- Joined
- Jan 26, 2010
- Location
- Rutherfordton
try rerouting your overflow tube directly into the reservoir.. I did that and it got the air out of mine.. Don't know why it wasn't pulling through the tube in the overflow, but..