jmj951

I had very bad injector leaks at one time. The PO had put silicone sealant in the seat around the injector o-rings on the manifold!! Completely ridiculous considering how cheap and easy-to-find the o-rings are (local Carquest had them in stock). Replaced the o-rings (and removed all of the silicone - very carefully since the intake manifold was not removed), and the fuel leaks were gone. Make sure you lube the new injector o-rings with a little oil (you may hear some conflicting info about this, but ultimately I found that engine oil was the most recommended lubricant for this).

While I had the injector leakage, I did not experience any of the engine problem symptoms you're describing.

How are you going to repair the thread? Helicoil?

Black51

I just went out and took a peek at my car. Have you looked at the fuel hoses, and the connection at the FPD. Notice how it's almost right above the #4 cylinder? So I'd look at that, sniff for gas, check the nut for tightness... Don't forget to use a flashlight, instead of a lighter for light in there.

If you still can't find anything, it may be a good idea to pull the fuel rail, or at least enough so you look at the bottom side for cracks, fatigue, punctures... Also, what condition are the fuel hoses themselves in? Again, the FPD hose leads right over the #4 cylinder. I'd disconnect it to look very closely at the bottom side. That's the thing with fuel leaks is they're the hardest to find and the most dangerous to have.

Adam Poland

No I have a spare intake manifold laying around. I may take my current one and make a custom intake manifold out if it just because I've got it. Thanks for the tip on putting the engine oil on the o-rings. Sounds like good advice.

Dang, I was going to use the Zippo. When i pulled the fuel rail the other night, I could not see any cracks or any fuel around the FPR. Ill have to check again under better lighting I guess.

Adam Poland

Update. I disconnected the tps, and no change. So it's not the tps. To ehall, the fuel lines are new, but I dont know about the fuel filter, I don't think it's been changed. It has a high volume fuel pump from LR. I fixed the injector problem, have found not one boost leak, and can see nothing electrical that would be causing the problem. The problem goes away when I turn the boost way down. When it cuts out under boost like I said, it goes SUPER lean...this has me leaning towards a fuel cut. Fuel filter?

Van

Why do you think unplugging the TPS would solve the problem? If that was the case, then why would the car have a TPS?

I had a similar problem - and it was the computer getting confused because the amount of air going past the AFM did not jive with the amount open the throttle was (at least the measured amount), so the computer thought there was a critical condition that needed fuel cutout intervention.

For what it's worth, the TPS I had measured good with a multimeter. I replace the TPS anyway, and the problem was solved.

Replace your TPS and let us know if the problem goes away.

Adam Poland

Will do, I tried replacing it and the throttle body with another I had laying around and it wouldnt even try to rev. I think that problem was the throttle body idle adjustment screw, (its stuck way high for some reason). I'm going to try replacing just the tps without the throttle body before I go and spend $125 or whatever it is on a new tps. In regards to unplugging the tps, I had the same thought, but tried it since ehall suggested it and I was really hoping to think I made some progress. I'm starting to think he had a typo or something in his post. Because if the same problem occurs with the tps disconnected as it does when it's connected, that would mean the tps is not functioning right.

Van

I've found that unplugging the TPS will give a KLR blink code... you can do that to make sure the KLR is checking for errors, and/or your blink code light is wired up correctly.

Adam Poland

Tested the tps, and everything checked out fine. But the problem is still there? I'm starting to really lean towards the fuel filter. We cant remember if we replaced it or not, so we probably didnt. A dirty filter would cause this, correct? The car sat for about 6 years before we bought it, so there could be contaminants in the tank that are getting cleaned out after cycling nothing but shell premium and one tank of straight 110 octane, and clogging the filter. Any contradictions?

Van

My thought is, if the fuel cutout is violent, it's being initiated by the computer. Either the computer is faulty, or one of the sensors giving parameters to the computer is faulty.

Fuel starvation, like a clogged filter, will just be a gradual reduction of fuel delivery.

Do you know anyone with a DME and KLR you can borrow?

Adam Poland

Makes sense. I have a few DME's and a KLR I can try. Since the problem I'm having is with the turbo, shouldn't that be the KLR? The reason I ask is that I dont know if my DME's are good or not. I know for a fact one is fried. But I know my KLR is good.

Edit: I forgot to add, when I let off the gas, my WBO2 gauge goes way lean, up to 21.7. It seems like it would make sense, but before this started happening it wouldn't go THAT lean, maybe to about 16 with no throttle applied, until the motor idled down. It seems to me like the fuel is being completely cut off when I let off the gas now.

Adam Poland

Took off my distributor, and some of the plastic on the rotor had worn away. Replaced rotor, no change. Checked coil, good. Plug wires, good. I guess I'll see if a spark plug is fouled. Oh, changed DME and KLR, no change.

ehall

Either way, you should change the fuel filter, if the car sat for a number of years.

minho78

TPS would exibit that issue I think. Or maybe the AFM or MAF is bad or not enough for the power you are making.

ehall

Do you have a MAF?

Adam Poland

Yes. The LR Quad-M. I'm taking the car to the RUF shop in Dallas on Friday. Tired of hunting this one down.