VandykeT/A

My 408 Trans Am is tuned for the previous set up (heads/cam/stock bottom/ 100mm maf sensor). Well I'm still using the same MAF as before and with a small hand held scan tool I show no codes but with the larger snap on (no clue what it is) I had a P0101 and a P1637 stored. I cleared them and nothing came back immediately. Is this normal for a car like that? The car is tuned for the MAF sensor I'm running just not this engine. I'm not really concerned about the P1637 since I dumped power steering fluid on the alternator and it is charging fine.

soundengineer

iTrader: (16)

it means whoever tuned the car has put the vehicle in Speed Density
P0101 is usually set when you fail the MAF in the tune

likely, the cam caused some issues with that MAF sensor and made it read funky and caused fueling issues....
big MAF sensors and aftermarket cams do not mix well

newer ECU's have some filtering built in to smooth the MAF signal
older ECU's (like in your trans am) do not have the filtering that the new ones do....and you get "reversion", which is basically the cam overlap breathing back thru the intake...and its gets picked up by the MAF and fueling goes all whacky making idle fueling not work properly and the car will run like crap...

the P1637 can also be an overcharging issue...meaning its always hot so it never shuts off or cycles