Round 2: Keepin' up with the Joneses, Mud Devils and Tony Woody

Correct. The constant connections go directly to the battery as per Holley
Just so I am clear... directly to the battery, or to the main cutoff/disconnect?
 
I havent messed with the switch pro units, but...I did trouble shoot and fix a similar problem with a buddy in a 5.0 (old school) in a hot rod running a holley sniper system.

Ill spare you the gory details of how much shit we chased, but his (again stressing wasnt a switch pro unit) was caused by EMF noise coming from the LEDs in the switch system panel.
Started troubleshooting with wires direct to battery and shit cleaned up...then broke out the scopes to understand why.
 
I havent messed with the switch pro units, but...I did trouble shoot and fix a similar problem with a buddy in a 5.0 (old school) in a hot rod running a holley sniper system.

Ill spare you the gory details of how much shit we chased, but his (again stressing wasnt a switch pro unit) was caused by EMF noise coming from the LEDs in the switch system panel.
Started troubleshooting with wires direct to battery and shit cleaned up...then broke out the scopes to understand why.
Local Holley guru tuner guy said to isolate the switched 12 direct to the battery as a quick test. Goes hand in hand with what you stated.
It's free and makes a little sense
 
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Batt positive and batt negative on the post. Referring to the 2 10ish gauge wires off the ECU
This is what I have done with other Holley systems, but those were in street cars. Are you going to run a battery disconnect on it? If so, what is running through it? Just switchpro? Maybe starter trigger? I know these are kind of stupid questions, but trying to understand how folks are wiring rigs these days, since I will be rewiring before long. In the past, my rigs ran everything through a disconnect, but they were minimal wiring with carbs or lpg.
 
This is what I have done with other Holley systems, but those were in street cars. Are you going to run a battery disconnect on it? If so, what is running through it? Just switchpro? Maybe starter trigger? I know these are kind of stupid questions, but trying to understand how folks are wiring rigs these days, since I will be rewiring before long. In the past, my rigs ran everything through a disconnect, but they were minimal wiring with carbs or lpg.
Good questions.
There is a battery cable from + to the disconnect. Output of disconnect goes to starter solenoid feed side. Also on the output side of the disconnect is the supply to starter switch and 6 gauge power supply to SwitchPros unit.
Yes, the constant power to the Holley is direct at battery and not effected by the disconnect. I did this since Holley clearly states go direct to battery. After I'm all done getting it running, I'll run the constand 12 to the disconnect and make sure it does ok there. If not, I'll leave at battery.
 
Good questions.
There is a battery cable from + to the disconnect. Output of disconnect goes to starter solenoid feed side. Also on the output side of the disconnect is the supply to starter switch and 6 gauge power supply to SwitchPros unit.
Yes, the constant power to the Holley is direct at battery and not effected by the disconnect. I did this since Holley clearly states go direct to battery. After I'm all done getting it running, I'll run the constand 12 to the disconnect and make sure it does ok there. If not, I'll leave at battery.

Leave it at the battery if you want to avoid issues. They don't really like power surges.
 
Isolated the switched 12v directly to battery as a temporary test- no change. Still loses cam sync while cranking. ECM sees RPM signal however.
Updated the handheld and the ECM software to latest levels.
Ugghhhhh!
 
Might be a pain to do but check continuity on the wires going to cam sensor. Move the cable around with the leads connected. The vibration of the motor turning over might be enough to disrupt the connection.
 
Might be a pain to do but check continuity on the wires going to cam sensor. Move the cable around with the leads connected. The vibration of the motor turning over might be enough to disrupt the connection.
Already done so. Ford uses the PIP output as a cam sensor signal, then doubles it to calculate crank speed
I have consistent voltage output from it.
 
Just so I am clear... directly to the battery, or to the main cutoff/disconnect?
The main cutoff of using large enough cable is the same as direct to battery. You must weld cable for this to be true, but equivalent
Already done so. Ford uses the PIP output as a cam sensor signal, then doubles it to calculate crank speed
I have consistent voltage output from it.
that little pip squeak is getting on your last nerve😂
 
I'd love to but I'm terribly swamped right now :(
You don't have a good tuner guy that could do it ?

I have a few recommendations but they're a ways out from you.

First thing I would do is isolate all the systems from the switchpros so you're not fucking with this on top of the rest.

Do you currently have no spark and/or no fuel ?
 
I'd love to but I'm terribly swamped right now :(
You don't have a good tuner guy that could do it ?

I have a few recommendations but they're a ways out from you.

First thing I would do is isolate all the systems from the switchpros so you're not fucking with this on top of the rest.

Do you currently have no spark and/or no fuel ?
Have spark, have fuel, just not coinciding appropriately.
I did isolate the circuits with no change in symptoms.
Doing a little research so I have a game plan when I venture back into the shop
 
If I can get an ADHD fueled hyperfocus on this, I'll figure it out :D Probably even have a dream about it.

If I do, I'll let you know. Then you can wine and dine me instead 😂
 
Gotcha. Is your ECU controlling timing ?


I would have been surprised


Smart
ECU controls timing beyond the base timing.
In an OEM 5.0 application, you remove a connector, set base to say 12*, reconnect and then the ECU handles advance. With the Holley, you lock it down, tell the ECU where it is and then select your own advance range you want to have.
That comes after I get it running with the base configuration though.
 
I'm assuming you tried to lock the timing in the software and start it up as is ?
 
dumb question.
Hows the battery?

Im throwing shit at the wall and haven't dove in to diagrams on this. But Ive seen issues before (even on very expensive industrial equipment) where a sensor has a very tight voltage tolerance and drops out due to voltage sag while cranking. Wonder the operatign range of the cam sensor
 
dumb question.
Hows the battery?

Im throwing shit at the wall and haven't dove in to diagrams on this. But Ive seen issues before (even on very expensive industrial equipment) where a sensor has a very tight voltage tolerance and drops out due to voltage sag while cranking. Wonder the operatign range of the cam sensor

Could be a thing for sure.
Under 10 volts during cranking I wouldn't bother.

Needs a good battery.
 
dumb question.
Hows the battery?

Im throwing shit at the wall and haven't dove in to diagrams on this. But Ive seen issues before (even on very expensive industrial equipment) where a sensor has a very tight voltage tolerance and drops out due to voltage sag while cranking. Wonder the operatign range of the cam sensor
Same thing happened with Megasquirt if voltage was less than 10
 
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