jmmcamaro2002

I have a stock 2002 Z28 Camaro and have search for a similar topic. I installed a WBO2 and I noticed that at WOT the engine was going lean (AFR=16.5). At 60 mph cruising, the AFR runs 14.5. I have notice that my LTFT are running high at about +20 on both banks at 60 mph. I have check the following:
1. Check the fuel pressure, which is good and increase with WOT run.
2. LTFT are essentially zero at idle and I have no evidences of vacuum leaks.
3. The LTFT banks are essentially equal and I have no evidence of exhaust leak.
4. The drive side O2 sensor was replaced.
5. I replace the fuel filter.
6. I cleaned the MAF very carefully.

I read in one of the post that you can tell if the MAF if failing by disconnecting it and resetting the trims and going for a drive. But it did not tell me how to interpret the data. I did this at 60 mph. With my MAF disconnected both banks of my LFTF read approximately +5. With my MAF connected both banks of my LFTF read approximately +15. Can I assume the MAF is failing? Is so, is there a good replacement MAF or should I just stick with the OEM?
John

dreww

iTrader: (1)

I assume no check engine light or codes?

if you have hp tuners, you can scan with maf hz as a variable. it should increase with throttle.

Russ K

iTrader: (1)

Your Maf has failed, replace it. Very common problem on a 12 year old vehicle,

Russ Kemp

jmmcamaro2002

Thanks for confirming that the MAF has failed. I had no codes and the maf hz increase with the throttle. There are a fair number of generic MAFs out there, does anyone have a recommendation.

LSX Power Tuning

iTrader: (4)

I agree

I have not had any luck with aftermarket maf's over the years. I have taken off more aftermarket maf's than stock ones due to them not reading right,

LilJayV10

iTrader: (39)

I'm having a similar issue but my LTFT's are -10 to -14 at idle, -5 or so when driving. My short terms are 0.

I disconnected the MAF and LT and ST were all 0 +/-5. Does this indicate anything or is this how it's suppose to act?

I don't mean to highjack your thread OP. I was going to start my own thread but found this one is close to my problem.

jmmcamaro2002

I bought a remanufacture MAF and that fixed my problem as I am no longer going lean at WOT. There were no codes that my MAF failed, but here is a graph of my LTFT for the old and new MAF.



@LilJayV10 Like you stated, at am currently running negative trims on the remanufacture MAF and I do not know if it needs to be corrected at this time. I am going to drive it for a while. I will be interested to hear if someone know the answer to your question, but I assume the remanufacture MAF is good, but may need to be tuned.

1970camaroRS

iTrader: (8)

Step 1. Remove your MAF
Step 2. Throw it in the trash
Step 3. SD tune for the win!

Mike454SS

iTrader: (4)

My 2000 Camaro failed in a similar manner...never threw a code, and it actually drove great with decent fuel trims until I stepped on it...then the car would go incredibly lean, knock, pull timing, fall on it's face...

Mike454SS

iTrader: (4)

That's how I solved it too...unplugged it...car ran great. Applied the HPTuners OS so it had high and low octane spark tables again since it was a daily driver and never looked back.

The stock VE table wasn't even that bad too lol...it needed a little work with the wideband, but nothing major.