LS3 TPS signal oscillates with recurring frequency image

[TRStech]

Hi all,

I attached a log of my 2013 LS3, stock mapping, headers, exhaust, airbox modified due to swap but not tuned yet. The engine is in a swap car, connected with the cars body control unit by a CAN translator. The translator also supllies the Acelerator Pedal Position by translating the OEM pedal?s signals. Engine is running complete stock tabels besides some DTC?s switched off.

Issue: Besides the fact, that engine runs quite well in my book I, noticed the oscillation of the TPS signal. The signal write seems to repeat each 5 intervals while performing 4 sharp peaks followed by one very short stable section. Sometimes 3 or 5 sharp peaks can be seen. This behavior is not depending on accelerator pedal pos, relative throttle pos or commanded throttle actuator. All of them behave normal. Only TPS is oscillating.

The wiring to the throttle body was prolonged due to 180 degree flipped TB position due to space reasons, so the TB is sitting upside down. I checked the wiring twice, no contact or risistance issues found. Checked TB connector to ECU connector.

Any ideas? Could it be an EMC issue caused by the spark wires?

[Alvin]

Stock throttle body?

[TRStech]

Yes, only flipped 180 degree. Besides that, complete Stock. At least as far as I know. The previous owner said it wasnt changed. But I wasnt able to find a GM part# on it. Well, it has a GM mark in the cast alluminum housing and the follwing number:

240205109_0069A

No google results. I didnt watch for a part number before I flipped it. Maybe its sitting on the former upside and I have to take it off to read it. The engine is taken from a 2013 Camaro SS EU export model.

[AlphaTuning]

Assuming there is no code for the throttle body/pedal and seems to work fine.. I have had this happen when I am scanning with multiple throttle position pids running or scanning the wrong one.

[TRStech]

Yes, no fault codes. Engine is behaving as it should in my book. Can you go a little depper what you mean with scanning or running the wrong PID? Meaning do you have a guess on which I should look therefore?

Thanks!

PS: Sorry for late replay, had to take care of some other issues meanwhile...

Edit: Nevermind, I changed the Input to "Throttle Position (SAE)", smooth signal on this one. Think you are right, just wrong PID.