Mert Celet

Hi Everyone,

Finally hot summer days have arrived and it's time to get back on the road with my 74 Firebird (98 fbody LS1, A4, (did 411 swap) 98 LS1 f body steel tank fuel system adapted to 74 steel tank). BUUUT... This fueling issue has been haunting me for such a long time and just this morning, it has got worse.

For such a long time, i had been trying to tweak out the fuel related problem as the car was running pig rich but with LTFTs Crazy Positive around +12-25
No matter how much i had added to the VE it never got better. And it was stumbling as if starving for fuel at higher rpms (especially after a 10mins of spirited driving around the mountains)

As of this morning, The pump primes, the car starts, no problem, in 30 secs, the world turns upside down. The engine starts to desperately try to maintain idle and dies. I restart it, does not start unless you press the pedal to the metal. And dies again. Whenever i try to keep the rpms steady with the help of the pedal, still dies. Even with a steady foot at the pedal, the rpms vary as if running out of gas. I've got sufficient fuel pressure, 48psi cranking, 60psi idle, 59psi wot)


I am trying to find out if this will take me to a dying pump, but this is a new racetronix pump with it's hotwire (checked everything cables, fuses,relay all ok) and there's only like 500 miles on this pump at most.

The issue was present with my previous pump (which was an og 98 fuel pump assembly) and JUST that i thought that it was like a symptom of a dying pump, i had converted to racetronix but again same issue. I though it was fuel starvation and installed Hydramat (more $$$ dumped) still there it was.

Anyway, here attached You can find my Log from this morning with many counts of failing. Sadly here in Turkey, no one knows **** about these cars and i'm all alone with my issue. If anyone can help me sort this thing out, i can not even express the amount of my gratitude. I have had this engine installed on this car for the past two years and never get to drive the **** out of it.

All the best
Mert

Lsxford

iTrader: (6)

Im pretty green with tuning but ill try to help you.

Check for exhaust leaks or vacuum leaks first. An exhaust leak will make the o2s read funny

Afaik if the fuel trims are adding fuel you need to reduce the numbers in your ve table. Say if the ltft is adding 15% subtract 15% or so from the ve in that area. May even help to reduce the maf table. Again however im very green to tuning. Sounds like its flooding to me. Im on my phone at the moment so cant look at the log. Ill check it out when i get home tho.

Also do you have a wideband on the car? Its a very useful device

Mert Celet

Someone said on the HpTuners Forum that i might have connected my O2 sensors opposite after my 411 swap. I'll give it a shot. I should have some O2 extension cables as leftovers at home. Hope it works out.
But whatever You do to add or subtract on LTFTs, it doesn't let you do that. It is constantly adding fuel without miss. I have added videos on my Youtube Channel.