02 lb7, check engine light

farmtough · 07-29-2008, 07:27 AM

i have a 2002 duramax lb7 and when i bought it, i had new injectors installed, and i had it for a week and it though a fuel pressure code at me and i cleared it and it was gone for a day and came back, so i changed the fuel filter and it was gone for and week and a half and it flashed it at me the other day and went back off. No code to read on my OB2 either, any suggestions?

**bigdaddydiesel** · 07-29-2008, 07:34 AM

Quote:

Originally Posted by farmtough

i have a 2002 duramax lb7 and when i bought it, i had new injectors installed, and i had it for a week and it though a fuel pressure code at me and i cleared it and it was gone for a day and came back, so i changed the fuel filter and it was gone for and week and a half and it flashed it at me the other day and went back off. No code to read on my OB2 either, any suggestions?

but I would suggest an after market fuel lift pump... that will help you to keep good pressure to the fuel rail pump to keep the fluctuations in pressure to a minimum.

**BigRedChevy** · 07-29-2008, 04:05 PM

What kind of mods do you have? Like bigdadydiesel said a lift pump will help, you may also need to shim your fuel pressure relief valve.

farmtough · 07-29-2008, 07:53 PM

i have and afe intake and a vanaken smart box 3 stage for mods, i just come home from a trip and it flashed the check engine light at me and when i scan it, it goes out on its own and does even give me a code to read in the scanner, it say no history either...........

**bigdaddydiesel** · 07-30-2008, 06:56 AM

I cannot give any advice for that, I have absolutely no experience with that programmer, but it does sound to me as if your programmer is trying to push more fuel than the system can maintain.

farmtough · 07-30-2008, 07:00 AM

is it going to hurt anything or is not a big deal? can i keep using it?

jaydawg · 07-31-2008, 06:37 PM

See if a Tech 2 can pull the code, or see the history.

**bigdaddydiesel** · 08-01-2008, 02:21 PM

MY experience??? If in doubt? Don't. too expensive a truck to trisk it... you could have a problem that costs you more than you really would like to spend. I would try my best to read the codes when they popup, maybe even switch programmers. sometimes they do not do as "Advertised"... either way, if you plan to keep making power with a programmer, a fuel lift pump would still be money well spent.