fuel trims at idle
05-29-2011, 02:25 PM
#1
Launching!
Thread Starter
iTrader: (3)
Join Date: Jun 2008
Location: richmond, va
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
fuel trims at idle im workin on an 02 ss and having some pretty wierd idle issues. i can put it in open loop and it itles fine at about 14:1 afr..i put it in closed loop and the ltfts and stfts all go to like - 15 and it leans out to like 20:1 and goes to running like crap. clear the fuel trims and it goes back to running fine for a second till the fuel trims get back way negitive. it looks like both o2 sensors are working fine but the car has idled fine in closed loop before and i havent changed anything in the tune. i guess if no one has any insite on here im gonna repmace both sensors.. there is no cel or codes. thanks in advance
05-29-2011, 02:42 PM
#2
Launching!
Thread Starter
iTrader: (3)
Join Date: Jun 2008
Location: richmond, va
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
replaced the sensors no change. both banks got to like -15 in a hurry but it looks like the sensors are readin right like 13:1 afr is around 800mv and 16:1 is like 350mv..why is it pulling fuel
05-31-2011, 09:45 AM
#5
Launching!
Thread Starter
iTrader: (3)
Join Date: Jun 2008
Location: richmond, va
Posts: 234
Likes: 0
Received 0 Likes
on
0 Posts
Slowhawk i didnt add many details because i was posting from my phone but thanks for the reply
Its a 2 bar speed density setup with 60 lb injectors. I looked last night i didnt save any good logs when i was working on this issue. I put it in open loop and everything is great. both o2 sensors are switching around stoich like they should. What else has influence on fuel trims? Both banks go to -15 in 20 seconds regaurdless of where the o2 sensors are reading. I replaced my wideband sensor just to make sure and its def lean...like 22:1.
I hope someone has some idea because im lost
Nothing has been changed that should effect this, afr command is 14:7 when it does this. Ive only changed VE PE the new boost enrich and both timing tables, Its a bone stock motor down to the valve springs
Its a 2 bar speed density setup with 60 lb injectors. I looked last night i didnt save any good logs when i was working on this issue. I put it in open loop and everything is great. both o2 sensors are switching around stoich like they should. What else has influence on fuel trims? Both banks go to -15 in 20 seconds regaurdless of where the o2 sensors are reading. I replaced my wideband sensor just to make sure and its def lean...like 22:1.
I hope someone has some idea because im lost
Nothing has been changed that should effect this, afr command is 14:7 when it does this. Ive only changed VE PE the new boost enrich and both timing tables, Its a bone stock motor down to the valve springs
