Got code P1516, & REDUCED ENGINE POWER during a race yesterday.
Conditions:
At mid track I lifted, then "quickly" gave it a little gas/lifted 2 or 3 times in a row to "play" with the other guy... Then the REDUCED ENGINE POWER popped up & I glided to the finish line..
I know I should be tapping the brakes instead of doing the multiple on/off throttle bit.. but, any thoughts on this?
Car drives fine, does not stall after spins or abrupt braking...
P1516 Command vs Actual Throttle Position Performance (TAC Module)
That code means the TAC(Throttle Actuation Module) is not getting the response it wants from the TB(Throttle Body).
The TB was not responding to the TAC inputs fast enough, or at all.
From what I was told there can only be a few percentage points of error in the response from the TPS(Throttle Position Sensor).
I wouldn't worry about it unless it happens again. If you want to try to recreate it you can do it with the engine off but key in the ON position.
Check the connection to the TPS sensor(Passenger side of TB), clean the grounds on the chassis you can see, and follow the harness from the TPS sensor back to see if there are any cuts or kinks.
Best case, it was a fluke and cleaning the grounds and checking the wiring it won't happen again. Middle case, you have a bad TPS sensor, worst case you have a TAC module going bad.
I had problems like this, turned out to be a bad wire in my case but I did buy a TPS and TAC to replace in case.
I have those items for sale if your problem continues and turns out to be a bad unit.
Good luck
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Winston Churchill
Air flow has nothing to do with the TAC wanting the TB blade at a certain position and the TB not being at that position.
The code you are thinking of I believe is 1518.
The TAC/TB/TPS are the things that cause reduced engine power, they are put there so if there is a mishap the car doesn't run away from you, its a "safety" feature.
Good luck
__________________
"You have enemies? Good. That means you've stood up for something, sometime in your life."
Winston Churchill
Air flow has nothing to do with the TAC wanting the TB blade at a certain position and the TB not being at that position.
The code you are thinking of I believe is 1518.
The TAC/TB/TPS are the things that cause reduced engine power, they are put there so if there is a mishap the car doesn't run away from you, its a "safety" feature.
Good luck
Oh really?
Then why did my car once go into REDUCED ENGINE POWER, as I did a fast spin in the water box & come to an abrupt stop?
Throttle cracker & VE table..
I don't know the answer, I was just looking for someone to "explain" it to me..
The TAC module is NOT bad, nor is the TPS sensor..
I feel its related to MAF airflow & speed.
Maybe someone else can chime in.
I said it was a possability that the TAC/TPS is acting up.
My information comes from my experience with similar problems on my C5 and from RoadRebel who is a forum member and worked on solving my problem with me.
He is pretty versed, if not one of the best versed, on the C5 and its electronics.
5 things according to him cause Reduced Engine Power. ONE of them is a airflow table problem and you did not set the right code for that.
The rest of them are all related to the throttle body.
How can the amount of air flow the MAF is reading, or airflow period have anything to do with the fact that the TAC module asked for X amount of throttle opening and you ended up with Y?
The TPS sensor is a dual sensor instead of single like on a regular cable driven TB. It has a default back up so you don't end up with a run away car. If your pushing down on the throttle 10 percent, the TAC is asking for 10 percent, but in reality the throttle is at 100 percent I think that is a pretty good reason to cut engine power. Its the whole point behind the dual fault system since there is no physical cable connection between the pedal and TB.
If those two fall out of tolerance for a short period then it sets the code. You popping open and shut the TB obviously caused this situation or one reason for another. You should be able to do what you did all day long, regardless of what it would do to your drivetrain you could do that until you shook parts apart. If you can't, there is a problem relating to one of those items.
You have a bad connection, bad ground, lazy TB, or a bad TAC/TPS.
__________________
"You have enemies? Good. That means you've stood up for something, sometime in your life."
Winston Churchill
Hook up a scanner and try to recreate the situation or something.
As far as reduced engine power,i got that when my fuel sending unit was all gunked up with sulfer.I think this also shows when the tranny kicks in the torque managment.
Corvette Store
Explain: Why I got P1516 DURING a race yesterday
i activated my TM one time at the track,but couldn't remember for sure if i saw the message.
