XJ injectors

upnover

upnover

Grumpy, decrepit Old Man
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Mar 20, 2005
Location
Morganton NC
Decided to make a thread just for this.
OK so today I am gonna try and install the injectors.
1st question until I get stumped and come ask another:

when I took the fuel rail out of the donor Jeep I noticed that around where the injectors were it was kinda rusty and grody. Not sure if mine will be like that, if it is, how should I clean it? Will it matter if some of the junk falls down in the hole? I am thinking that if it does, it should go on out the exhaust.
BTW the donor injectors look nice and shiney where the sprayer is
 
Junk falling into the fuel rail is bad. If it falls into the intake manifold, not good, but i wouldn't worry too much. Since you aren't re-using the o-rings, hit the area with brake-kleen and then compressed air to clean the area. If you were gonna re-use the orings, i'd worry that it would damage the rubber and/or viton oring. Might be worthwhile to pop the pressure regulator off, flush the fuel rail, and replace the orings on the pressure regulator. And a new Fuel filter is always a good idea, especially if you're already doing fuel system maintenance
 
Get the o-ring kit for the upper fuel line, too. I replaced injectors twice, and both times could only find that kit at the dealer. It's on a little break-away plastic stick that you use to install it. It makes sense when you see it, but I bet this post is pretty confusing.
 
Well, some of this would have been helpful before I did it. But the good new is, no more leaks. I took all the injectors off the rail, cleaned the gunk from around the o-ring mounting surface, lubed them all up, put on the new o-rings, lubed again, and installed the rail and injectors.
Now it has a lope, a big fluctuation in the idle. Sounds like crap. Maybe I got something in the injector? Maybe they have sit too long and are no good? I don't know.
Think fuel injector cleaner would help?
 
When I finished my last injector swap, the thing ran like crap for a while. It eventually evened out after I re-did the exhaust, and replaced a cracked muffler. YMMV.

I don't want to tell you that the on the first XJ I swapped injectors, I never could get it running right afterwards.
 
Run a can of Seafoam through the intake. If its a dirty injector it should take care of it. Wouldnt hurt to run one through the gas tank either.
 
Sounds like a vacuum leak or a bad injector. Lightly spray carb or brake cleaner around the injectors to see if the idle changes.
 
upnover said:
OK school me here, what is "seafoam" ??
Click to expand...

snakeoil in a can

some people swear by it, to me, it's just another couple $$ given away to the parts store. It's supposed to help clean built up gunk out from the inside of your intake, off of the intake valves etc.
 
It actually works quite well... when used for cleaning carbon,etc. out of the engine (letting the brake booster or other full vacuum source pull it in while holding the engine wide open) That being said, I don't think it works that great for an injector cleaner (pouring in the gas tank)
 
I think it has to be something in the injectors, or a vac leak. Was running good before I did this, just seeped gas out of four injectors.
Do you think it might be the fuel regulator? I had a new one on the old system, but didn't switch it over on this one. I used the one that was already on it.
 
Oh, I just remembered.... I had a couple injectors that I didn't get seated properly. They can be real hard to get into the port -- those new o-rings are big. Can you check to make sure they're seated? They should take some elbow torque to get in.

I'm trying to think simple first.
 
Check for a vacuum leak first, then check your fuel pressure since you said the regulator was on the fuel rail.
 
Found it!

OK, well I didn't. David Minton of Minton's Automotive did. Vac line going to the intake for the MAP sensor.
 
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