Car runs badly
Thread Starter
Racer
Joined: Apr 2010
Posts: 275
Likes: 1
From: Phx Az
Car runs badly
Tried search,and wound up trying to get information from an old thread.Needless to say that was a dead end lol!
Any how here's my issue.My 01 coupe has always had a hesitation under accel (bought it used about 3 mons ago),and will detonate like a mad demon if you try to go wide open on it.You could roll into it steadily and get away with running it to redline,but not mat it at all.
Yesterday it got way worse,and would not accelerate past 2 grand without all kinds of protest.It revs freely in neutral,but did not want to accel under load.It would buck and hesitate,and lose power,then find itself and go.Was wondering if this is a maf problem or what others may have experienced,so I'm not just breaking out the shot-gun and throwing random parts at it.
It also should be mentioned that it turned on the check engine light and gave me the lean bank1 and bank2 codes.
Your experience and knowledge is greatly appreciated.
Any how here's my issue.My 01 coupe has always had a hesitation under accel (bought it used about 3 mons ago),and will detonate like a mad demon if you try to go wide open on it.You could roll into it steadily and get away with running it to redline,but not mat it at all.
Yesterday it got way worse,and would not accelerate past 2 grand without all kinds of protest.It revs freely in neutral,but did not want to accel under load.It would buck and hesitate,and lose power,then find itself and go.Was wondering if this is a maf problem or what others may have experienced,so I'm not just breaking out the shot-gun and throwing random parts at it.
It also should be mentioned that it turned on the check engine light and gave me the lean bank1 and bank2 codes.
Your experience and knowledge is greatly appreciated.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
Lean codes come on only during P/T operation when the ECM is in "closed loop" and is running off the 02 sensors trying to correct the AFR to 14.68 via the fuel trims---To throw a lean code means that it is asking for more than 25% additional fuel to correct--that is the limit and then you get a code--- make sure your 02 voltages are oscilating rapidly between .100 to .950 millivolts--you'll need a scanner or tuner--
Most likely they are flatlined at .450
You should check you MAF make sure you didn't over oil the filter as that will foul the MAF--clean with brakeclean-- Also check for a vacuum leak--the MAP pigtail on the back of the manifold --TB inlet clamps--You could be getting un-metered air into the engine--
Most likely they are flatlined at .450
You should check you MAF make sure you didn't over oil the filter as that will foul the MAF--clean with brakeclean-- Also check for a vacuum leak--the MAP pigtail on the back of the manifold --TB inlet clamps--You could be getting un-metered air into the engine--
Thread Starter
Racer
Joined: Apr 2010
Posts: 275
Likes: 1
From: Phx Az
Lean codes come on only during P/T operation when the ECM is in "closed loop" and is running off the 02 sensors trying to correct the AFR to 14.68 via the fuel trims---To throw a lean code means that it is asking for more than 25% additional fuel to correct--that is the limit and then you get a code--- make sure your 02 voltages are oscilating rapidly between .100 to .950 millivolts--you'll need a scanner or tuner--
Most likely they are flatlined at .450
You should check you MAF make sure you didn't over oil the filter as that will foul the MAF--clean with brakeclean-- Also check for a vacuum leak--the MAP pigtail on the back of the manifold --TB inlet clamps--You could be getting un-metered air into the engine--
Most likely they are flatlined at .450
You should check you MAF make sure you didn't over oil the filter as that will foul the MAF--clean with brakeclean-- Also check for a vacuum leak--the MAP pigtail on the back of the manifold --TB inlet clamps--You could be getting un-metered air into the engine--
I guess I'll have to find my cartridge for my snap-on mt 2500 and check my o2 values etc.I know the intake was off for the oil sender at the dealer,maybe they didn't hook everything back up correctly or didn't bother to see a bad vacuum connection,although the problem was there prior to the o.p.s. being replaced.I'll also clean the maf,but i'm still stone stock(air intake etc.).All connections on the front side are tight and in good order.
So I guess I have some investigating to do....
Any other ideas are appreciated.
