??Pulled engine codes tonight
Thread Starter
Racer
Joined: Aug 2006
Posts: 492
Likes: 0
From: Minnesota
??Pulled engine codes tonight
My 96 LT4 has had a check engine light on and off and more on than off lately. Car first had a strong fuel odor that i couldnt find a reason for. Then, the car would start to run rough and idle poorly. Then, now if its warm (or especially has been driven awhile) it barely starts. Or maybe i should say it starts but dies within seconds, unless i keep giving it throttle/gas. But! If I can get on the highway and heading down the road for a few miles it will stay running/idle. Granted rough, but will drive. SO I went and pulled the check engine codes and the codes were: Random misfire, and Too lean bank 2. I'm mechanically inclined and do all of my own wrenching. But, looking for some knowledge from the members here on where to start?? Even though I can sometimes smell a strong fuel odor and that would make sense for the too lean fuel bank, I have never been able to find an actual fuel leak anywhere. So?? Any thoughts?
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
The "lean exh indicated" code could also mean the O2 sensor is faulty.
The ECM is seeing a lower voltage than it expects to see which may be caused by a bad sensor and not that the engine is actual running lean
For earlier (OBD1 ) cars but analysis the same
http://www.mifbody.com/DTCs/DTC%2044.jpg
What were the DTC # you actually pulled?
The ECM is seeing a lower voltage than it expects to see which may be caused by a bad sensor and not that the engine is actual running lean
For earlier (OBD1 ) cars but analysis the same
http://www.mifbody.com/DTCs/DTC%2044.jpg
What were the DTC # you actually pulled?
Last edited by rodj; Aug 2, 2011 at 07:56 PM.
Safety Car
Joined: Sep 2010
Posts: 3,752
Likes: 190
From: Indiana PA
Bank two should be the passenger side, I think...whatever side cylinder 1 is is bank 1 and cyl. 2 is bank 2.
If you can see it, which ever bank is more forward in the car is bank 1.
I'm going my memory here and I have CRS.
Yes, logically, if you only have a bank 2 lean code, then fuel pressure might be ok. Better to be sure than not. Then again with a random misfire and a lean bank 2, how you do know it is NOT a fuel pressure issue or insert whatever you want here.
Four things I have learned working on cars is A: Never assume anything B:If not not sure, test until you are. C:Often times things defy the Service Manual and Logic. D: Cover your basics first and remember the KISS principle.
If you can see it, which ever bank is more forward in the car is bank 1.
I'm going my memory here and I have CRS.
Yes, logically, if you only have a bank 2 lean code, then fuel pressure might be ok. Better to be sure than not. Then again with a random misfire and a lean bank 2, how you do know it is NOT a fuel pressure issue or insert whatever you want here.
Four things I have learned working on cars is A: Never assume anything B:If not not sure, test until you are. C:Often times things defy the Service Manual and Logic. D: Cover your basics first and remember the KISS principle.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette & Porsche 911: How Two Icons Conquered the Last 25 Years
Joe Kucinski
2027 Chevrolet Silverado 1500 First Look: Everything You NEED to Know!
Michael S. Palmer
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
Instructor
Joined: Mar 2010
Posts: 163
Likes: 0
From: Birmingham Alabama
If its showing a 'lean condition' the PCM will try and compensate by adding more fuel, hence the fuel smell. Or the missfire could be allowing unburnt fuel through the exhaust, again fuel smell.
It does sound a lot like an O2 problem, if the sensor is still within range, it won't throw a code, but still being within range can be significantly off to cause problems.
Sara Lou
It does sound a lot like an O2 problem, if the sensor is still within range, it won't throw a code, but still being within range can be significantly off to cause problems.
Sara Lou
Thread Starter
Racer
Joined: Aug 2006
Posts: 492
Likes: 0
From: Minnesota
Well, I replaced the MAF. Reset the engine codes. Drove great for about 20 miles. Shut it off and waited for an hour and restarted fine, so i thought i was in the clear! Then took it for a little spin, shut it off and it wouldnt start and idle
, unless i hold it at about 2500 rpm. Even then its really really rough. And the check engine light came on. so went and pulled the codes again. Random misfire, and cylinder 06 missfire.
So at this point it seems the MAF took care of the lean condition. But! Now the missfire codes????? Im also believing when you give it full throttle it seems to run perfect, which makes me wonder if it isnt a sensor that goes close loop at WOT. And what is with this runs fine til you restart it???
, unless i hold it at about 2500 rpm. Even then its really really rough. And the check engine light came on. so went and pulled the codes again. Random misfire, and cylinder 06 missfire.So at this point it seems the MAF took care of the lean condition. But! Now the missfire codes????? Im also believing when you give it full throttle it seems to run perfect, which makes me wonder if it isnt a sensor that goes close loop at WOT. And what is with this runs fine til you restart it???
Last edited by Huntervangolf; Aug 8, 2011 at 01:52 PM.
