Many problems all at once please help guys

**2000ws6 (703)** · 06-04-2009, 02:09 PM

I have a 2000 ls1 camed heads the works. anyways my check engine light has allways been on and when it finally went away the car started falling on its ass around 5000. Ran perfect before 10.90s. I have a pretty new fuel pump in walbro 255. and i checked the grounds, i can basically disconnect all the sencers map, fuel return sencer and nothing happens and i am not running mass air flow its tuned with speed density tune. I am making anywhere between 20 to 55 psi of fuel pressure very inconsitentent, and its backfireing thru the intake and missing through out driving range. also alternator is not charging. any one know what would effect all this? The car will barly beat a minivan now. no knocks or troble codes.

**c5z28** · 06-04-2009, 02:17 PM

O2 sensors can be bad. If it is showing the ses get the codes read by someone or by a gm dealer if you have to that will take the guess work out of it.

**cammed goat** · 06-04-2009, 02:59 PM

Originally Posted by c5z28

O2 sensors can be bad. If it is showing the ses get the codes read by someone or by a gm dealer if you have to that will take the guess work out of it.

I agree. Car is basically coughing.

**2000ws6 (703)** · 06-05-2009, 06:57 AM

Thanks for the advice i actually tried that lol. but yesterday i messed with it. I think i have 2 problems a weak alternator and a pump that is failing. that seems like it would throw everything off with low fuel pressure and specally not charging the battery up. This is the second pump ive used that was a walbro 255. Ive had nothing but problems with them. any recomendations on a good fuel pump?

**0rion** · 06-06-2009, 11:03 AM

sounds like your pump to me....sounds like you're running out of fuel. You want 58psi on that pump....20 is too low. I run the racetronix kit and have been happy with it.