Hogdady

01' Trans Am LS1. Just replaced MAF and now the engine has severe hesitation under moderate to hard acceleration. Did notice that MAF removed had no screen and new (Cardone) replacement does. Put original MAF back in and acceleration issue goes away. Any ideas?

bene

iTrader: (16)

Why did you replace a perfectly good running stock MAF?

Hogdady

Been having some intermittent poor running/stalling and hestitation issues coupled with lean fuel codes (PO 171, 174).

bene

iTrader: (16)

I'm guessing you cleaned the stock MAF sensors already? Checked/replaced your fuel filter, did all the maintenance tune up?

Hogdady

Cleaned OE MAF but it didn't clean up as well as I wanted. Was running a K&N but changed to paper today. Fuel filter, iridium plugs and wires yesterday. Below is the thread I posted which led me to change the MAF.

https://ls1tech.com/forums/pcm-diagn...ower-loss.html

bene

iTrader: (16)

That's the thing... the only way to know your stock MAF sensor is bad is when you unplug the harness and drive it. It'll go to SD tune and if it drives better sans the MAF operating, you have a bad MAF. Or switch it with another one.

That code says it is leaning... Possibilities are: unmetered air going inside your engine, bad MAF, bad fuel filter/pump- not enough fuel or clogged injectors and O2 sensors aren't switching.

Old Geezer

iTrader: (3)

Cardone maf????

Have you done a data log and captured the fault? What's the maf freq doing?

BLK02WS6

iTrader: (2)

If the one you took out had no screen, then possibly the car was tuned for that?? and replacing it with a stock one will cause the tune to be off... Like said above, unplug the MAF, run it in SD and see if your lean code was due to the MAF or one of the other causes... if code still comes in during SD, I would go back to the original MAF as that is not the cause.