Engine/Transmission (1998.5 - 2002) Air in lines!!

[jerrethomas]

I was out for a drive today and was playin around a bit. I had the comp on 2x3 smarty on 8. Shifted through the gears normal till 4, grabbed 4 and mashed it for about 150 ft or so and then let off, when i let off it died. I coasted to the side of the road and had no idea what to do. I had good fuel pressure at the vp-44, idle about 16, wot about 12 before it shut off. Cranked the heck out of it nothing, called one of my buddies, figuring on having to trailer it home, due the injection pump went out, but had no codes. He grabbed a wrench and and cracked one injection line, i cranked it, had fuel also some bubbles. When i knew that i know i had air in the lines. Bleed 2 other ones and then i fired up. What makes it do this and can it be fixed. I always have good fuel pressure so it's not like it has to pull it own fuel. Had me worried for a while.

 

[AKAMAC]

Make sure there are no leaks on the return lines from VP or input/pressure side of fass system. Sounds like you sucked air from somewhere. I'm not familiar with the fass pressure relief mechanics, so I won't offer an opinion on that. Mike

 

[WestTN]

Was the fuel level in the tank low enough that you uncovered the pickup on hard acceleration?

 

[OPoole]

I call that vapor lock it happens when your in it hard and lift quick. Best thing is to roll start it back or carry a can of starter fuild i keep a can in each truck. And if i'm going test driving something hard i take one! I have had to walk back before.

 

[jerrethomas]

Was the fuel level in the tank low enough that you uncovered the pickup on hard acceleration?

nope, full tank.

 

[jerrethomas]

I call that vapor lock it happens when your in it hard and lift quick. Best thing is to roll start it back or carry a can of starter fuild i keep a can in each truck. And if i'm going test driving something hard i take one! I have had to walk back before.

Is there any way to fix it or just have to roll out of it slowly? We did spray either in it but didn't make much of a difference. maybe because it had to go through the air cleaner and through all the pipes, not to sure though.

 

[OPoole]

Best thing i can tell you is to round out of it easy. Some truck are worst than other and some never do this? I do not know of any fix sorry.

 

[LowFly]

maybe because it had to go through the air cleaner and through all the pipes, not to sure though.

DOOOOOOOD! DONT EVER DO THIS!!!! IF that crap lights... . you are going to be out an intercooler, turbo, and... ..... pray it dont take your head off while its doing it!



Always pull the intake horn boot off and pull the wires for the intake heater to disable it. Then shoot it with a small amt of either! Takes WAY less cranking as well.



As for your issue, I have seen this on a few trucks. Never though about it like Olee put it but makes sence. I have seen some new FASS installs do this... but it was like 1 day after, and the truck would die right after a WOT run. I feel this was an air pocket that was working its self loose in the lines after the first inital install. This could happen if you have a small leak somewhere... . might brake out some clear hose for testing if the prob comes back more often.

 

[jerrethomas]

DOOOOOOOD! DONT EVER DO THIS!!!! IF that crap lights... . you are going to be out an intercooler, turbo, and... ..... pray it dont take your head off while its doing it!



Always pull the intake horn boot off and pull the wires for the intake heater to disable it. Then shoot it with a small amt of either! Takes WAY less cranking as well.

I am well aware of the affects of either, i work with it on a daily basis at our shop. I was cranking it before it was even sprayed and the engine temp was about 170, so the grid heater shouldn't have been on. No time delay between turning the switch on and cranking it either. Due to lack of tools it didn't take the boot of the intake horn to spray it in or i would have.



Also, i'm not aware of any leaks in my fuel system. I put a fuel filter in on friday afternoon, and this happened on sunday. I didn't have any problems in between though.

 

[Ncostello]

Upon my in depth study of the fuel pickup module on these trucks... and knowing what goes on even with a low tank level... you'd almost have to hit a brick wall with only a gallon of fuel left to make the fuel escape the module. The module holds fuel itself for some short period even if it runs away from the pickup location. FWIW and from what Ive seen.

 

[ces944]

All I gotta say is you better thank that friend with the wrench that came to help ya out :-laf

 

[jerrethomas]

All I gotta say is you better thank that friend with the wrench that came to help ya out :-laf

Thank god for ya curt, I was pullin my hair out real quick.

 

[Smokewagon359]

All I can say is that I feel for you. My truck has comp, stage four, vulcan draw straw and big lines all the way to the pump. I've killed mine at least 6 times in the last year, and yes it seems to be better if I let out slow. I know none of this is any help, but I just wanted you to know "you ain't alone"