Hi guys need some of your wisdom. Engine partial shuts down and says :Reduced Engine Power" on startup.

First thing: Last night it was about 32 deg out, essentially freezing and I started the car it started no problem let it warm up for 2min and I think I touched the gas just to see how it would respond and it went into "Reduced Power Mode" It sounds like it runs on 4 cyl or something. I promptly shut the car off and let it sit for a minute.
- I then started it again and it basically started in "Reduced Power Mode" I shut it off after about 15 seconds of listening and trying the gas.
- I waited about another 7 minutes while reading the manual... found nothing and started it everything was fine and drove home with the yellow engine light on.

Now this morning I start it basically same as above all over again...

I read something somewhere once about oxygen sensor on aftermarket exhaust having this issue or something…


Did some searches but no body with same problem. Looks like you can't get the DTC info on the C6 either...

Dealer told me the Error Code was "P2101" or somehting to do with "TAC"

Thanks!!!

 

i need a code to help

 

All it tells me is "Reduced Engine Power"

Doesn't give a specific code,

I heard the C6 doesn't give out DTC's ...

Thanks for any help guys,

 

you will need a scan tool

 

The Dealership said it is: P2101 or something to do with "TAC" Throttle Actuator Controler.

They ran through all the wires and "wiggle tested" for loose connections. And said if it happens again to come back.

I have a CAI and a Fast 90 not sure if either of these are effecting the throttlebody.

Thanks for any feedback.

 

Ok typically you will get some sort of error such as this when airflow modeling does not match OEM tps for a given load.
So the FAST may may pushed you deeper into the realm but the weather may have pushed you beyond the threshold. Take for example if a supercharger were installed the moment you go into boost it will trip the same error. Too much Airflow for a given TPS. Easy fix set the TPS thresholds in the tune up out of spec.
You need to set the codes P0068, P0106 and P0121 tests way out there so you dont meet the criteria of the possible error codes.
Jeremy Formato

Thank you and God bless

 

Man I love this forum!

THanks for the reply.

 

the second post above means when getting a tune, to turn off those codes? my car has done this same thing twice now in two weeks. its bugging me.

 

If you have OnStar, call them and ask for the code when you have the problem. I got an SES and called them. They told me the code and my issue wasn't "serious" and I could drive the car and visit the dealer at my convenience. I would imagine they could help you. If nothing else, leave it in that condition and have a tow truck take it to the dealer.


Elmer

 

Same problem here.

I set the General > TPS sensor positive and neg to 7%
Does that narrow the range to eliminate it?

Did not see a P0068 test, only the Dx tests for P0101,P0106,P0121 which I set up high.

 

how do you set these up high? the above posts are confusing me. can someone put this in dummy terms for me?

 

Sure man. These are different Dx codes which sets the CEL and an OBDII scanner picks up. The question relates to setting the parameters which turn these on and off be means of a tuning program, ie HPTuners.

Since turning these parameters off in the diagnostic section of the tuning program will not avoid the dreaded "reduced engine power" warning, the answer is to set their parameters to a level they won't be triggered. It's all in the tuning program.

Since I have had TPS problems, with the damning "reduced engine power" function, at the track, I am interested.

My question is: did I set P2101 correctly, at 7% for positive and negative TPS sensor? I hope so.

Regarding P0101,P0106,P0121 those are turned off by setting the ECT high. Then the P0068 is set by the PRM level, I have that at 8,000.

 

These are usual codes for poorly ported TB's. Since there are gobs of ported FASTs and ported TB's out there, I will say something is wrong in that dept.

 

Mine did the same thing when i ws trying to get voltage on a WOT wire not too long ago..I jus unplugged the battery and it went away nothing major on my end luckily...good luck with it man..

 

That is likely. Now, this happens only after a 20 min hard track run.

The larger (100 mm) TB I put on my LS7 has a TPS for an LS1. There is no one to ask who has done this. Can you tell me, as a tuner, where to set the P2101 to eliminate this table comparison? It is at 7% for positive and negative TPS sensor. Should I set it at 0%, 90%, 110%?

 

bump for the above ?'s my tuner used HP as well so i wanna make sure when i go back to him, i know what to have him set this stuff at.