Engine/Transmission (1998.5 - 2002) Truck Stalls When Comp on 5x5

[1FSTDSL]

Twice now, I have had my truck quit on me after a hard run on 5x5. Both times the truck just died as I come to a stop at the light. I have to crack open a couple lines and bleed it to get it running again. Any ideas?

 

[Gary - K7GLD]

What is your fuel pressure under those conditions?

 

[1FSTDSL]

I maintain 16-17 psi. This only occurs occasionally and it seems to happen when I get on the throttle briefly and let up. It is like I get air in the system, but I can't imagine that I would be.

 

[Big P]

This happens to me too. Do a search in the competition forum, there was a thread about this. I wouldn't say it's common, but it's not unheard of either. It seems the only solution is to back out of the throttle easy to avoid stalling. A local shop said it was a bad injection pump, so they replaced it and the new one does the same freakin thing. Just have to learn to drive around it.

 

[YEEHAW]

This happened to me too. Except I got a "No Communication... " code and cannot get it to start. I think my pump is done.

 

[PC12Driver]

Letting off easy is the key. My truck started doing that after I put the injectors in. Mine never completely died, but I could tell a couple of the lines had lost their prime. They'd come back with a couple of blips of throttle (no codes). Since then I've trained my right foot to stop at 1/4 throttle for a moment when letting off after a high boost run and haven't had the problem since. Probably easier on the turbo, too.



And I keep a 19mm wrench in the truck just in case...

 

[Big P]

Originally posted by PC12Driver

And I keep a 19mm wrench in the truck just in case...

Me too!

 

[Chipstien]

Originally posted by PC12Driver

And I keep a 19mm wrench in the truck just in case...

Make that three of us... . though the only time I have needed it was when I ran out of gas once... .

 

[1FSTDSL]

Originally posted by Chipstien

Make that three of us... . though the only time I have needed it was when I ran out of gas once... .

Maybe that was your problem, you were putting gas is your truck.

 

[Gary - K7GLD]

I have seen pretty consistent demonstration of LP cavitation when the pump is exposed to near-maximum pressure with severely restricted flow - and when it does that, it would NOT again return to normal flow even when the restriction was removed - sorta like it lost prime and was air-bound. Only way to restore normal operation was to shut it down and restart - this was on a test bench - but I can see that entrapped air produced from cavitation due to suddenly letting off the accellerator MIGHT do the same thing, and that then any air present could create running/starting problems...

 

[PC12Driver]

I wouldn't think that the fuel in the injector lines would have enough momentum to create a low enough pressure for cavitation when the pedal is released (since there's nothing else pulling on the fuel on the injector side of the pump).



I wonder if there's a chance that the cylinder pressures are substantially higher than the pressure in the fuel rails for a split second when the throttle is released and some of that gets pushed back passed the injectors into the connector tubes.



Dunno, just throwing that one out there...

 

[Big_Daddy_T]

I kept a 19mm under my seat.



Mine would do it predictably. Most of the time it would just stall and not air lock. Sometimes it would air lock. Mighta done it twice a month at 200+miles a day. I think I had to use the wrench maybe 3 times. The first time was the pain. Had to walk to the auto shop to buy the wrench. I was worried it would damage the injection pump. I never had any problems though.