So I dropped in 2nd, punched it and it got to 5000 and cut off and check engine light came on and it said Engine Power Reduced....The car wouldnt go anywhere, it shaking and the idle was surging....I scanned it...and got MAP sensor codes and MAF codes and air/fuel metering codes....Pushed to the house...let it sit for an hour or so...started it back up...check engine light was on then went out by itself...took it down road and ran through all the gears...and pulls perfectly fine.......Basically the point Im trying to make here is that this is the second tiem that this has happened...both times it was about 105 degrees outside and had been running through the gears a couple times. What could be causing this intermittent problem????? I got 2.8 60's and injen, stock exhaust still.

 

unplug battery for 10 minutes so it reset the computer

 

some kind of saftey mode?

Ive heard that the maf's are bad on our cars. replace it and see if it happens again.

 

Usually caused by an induction air leak. Check your piping, gaskets and vacuum lines.

If its custom tuned I would put money on it being a poor tune. Reduced engine power means that the 4 airflow sensors (SCIP, TPS, MAF, MAP) aren't all showing expected readings. Since a custom tune is basically a calibration of one or more of those sensors, it may be inaccurate values causing reduced engine power mode.

Our MAFs are some of the most accurate produced. Its the software calibration that causes them to report incorrect values 99% of the time.

 

accurate, yes. i agree, but that does not mean that they dont need to be replaced from time to time. especially since he has a aftermarket intake and the maf has been fiddled with. its a easy fix. and a cheap fix.

 

Because its a digital sensor, frequency based MAFs in my personal experience usually either work or they don't. I have yet to stumble upon a frequency based MAF that would skew or report inconsistantly without throwing p0102 or p0103.

 

Are you running a CAI with a oiled filter??? This can and will fry you MAF sensor in a heartbeat, just a thought.

 

I totally see what you guys are saying...but its only happened twice...and both days it was 100 plus outside. I have the pulley and intake for like 6months now

Its not oiled.

 

If you go over the set maf frequency it will seem like you hit the rev limiter. I had similar mods and I had my car go into reduce mode twice. I had to up the frequency limit with HpTuners for the issue to go away.

 

I did get a custom tune but it runs great for months at a time, then one day it will do it, Ill turn the car off let it sit and then its fine for another couple months

 

I dont know man. Just thought you were having the same issues I was having.

 

Would it happen all the time to you?

 

Rarely..... I had the car like that for 8 months and it happened only twice. If you can hook up with your tuner ask him to increase the "Maf fail high" to the max. If you have thrown code p0103 then this might be the issue. If you have any issues pm me.

 

I had the same problem its the throttle position sensor.

 

I also had this happen to me when I put on my 2.6" pulley. I took it 2 my tuner & they said this is common when u try to modify current year GM cars too much like GTOs and Cobalts but especially GTOs. Its called "torque managment". I took mine to my tuner & had them disable it & it has never done it since. If ur running a 2.7" pulley or smaller get it disabled bcuz exactly what u descibed was happeng to me when I put on my 2.6" pulley.

 

What is all the fuss about "torque managment" for SS/SCs?? It's for automatic transmissions only, and changing that does absolutely nothing for us. Hence why GM removed it completely from the 2007 ECM.