Limp mode 2000 C5
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From: Supply, NC
Limp mode 2000 C5
Hi guys, I'm working on my buddies C5 base Vette. He bought it in limp mode. Codes are p1120, p1220, P1516.
New tps
NEW app sensors, have checked wiring, when I test new tps, the readings are fine with throttle blade closed and at wot, however when the throttle blade is opened to say 30% to 70%, the voltage reading are all over the place. Whoever was working on this car put a TAC module off a 07 Silverado on this car, I have the one that belongs to the car but it's been ripped open, it looks fine inside. Motherboard looks good nothing burnt. If any of you guys know why the tps readings are so erratic during mid travel of throttle blade, please suggest something. Also when I manually open TB it's smooth, no extra play in shaft and its clean. Any suggestions are greatly appreciated, 80k miles on car, thank you, Michael
New tps
NEW app sensors, have checked wiring, when I test new tps, the readings are fine with throttle blade closed and at wot, however when the throttle blade is opened to say 30% to 70%, the voltage reading are all over the place. Whoever was working on this car put a TAC module off a 07 Silverado on this car, I have the one that belongs to the car but it's been ripped open, it looks fine inside. Motherboard looks good nothing burnt. If any of you guys know why the tps readings are so erratic during mid travel of throttle blade, please suggest something. Also when I manually open TB it's smooth, no extra play in shaft and its clean. Any suggestions are greatly appreciated, 80k miles on car, thank you, Michael
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From: Cape Coral, Florida
Hi guys, I'm working on my buddies C5 base Vette. He bought it in limp mode. Codes are p1120, p1220, P1516.
New tps
NEW app sensors, have checked wiring, when I test new tps, the readings are fine with throttle blade closed and at wot, however when the throttle blade is opened to say 30% to 70%, the voltage reading are all over the place. Whoever was working on this car put a TAC module off a 07 Silverado on this car, I have the one that belongs to the car but it's been ripped open, it looks fine inside. Motherboard looks good nothing burnt. If any of you guys know why the tps readings are so erratic during mid travel of throttle blade, please suggest something. Also when I manually open TB it's smooth, no extra play in shaft and its clean. Any suggestions are greatly appreciated, 80k miles on car, thank you, Michael
New tps
NEW app sensors, have checked wiring, when I test new tps, the readings are fine with throttle blade closed and at wot, however when the throttle blade is opened to say 30% to 70%, the voltage reading are all over the place. Whoever was working on this car put a TAC module off a 07 Silverado on this car, I have the one that belongs to the car but it's been ripped open, it looks fine inside. Motherboard looks good nothing burnt. If any of you guys know why the tps readings are so erratic during mid travel of throttle blade, please suggest something. Also when I manually open TB it's smooth, no extra play in shaft and its clean. Any suggestions are greatly appreciated, 80k miles on car, thank you, Michael
Other than an OEM sensor would be suspect…I’d also check the connector and the sensor grounds for each TPS sensor…should be less than 100 millivolts…try wiggling the connector between that 30-70%.
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Joined: Apr 2019
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From: Supply, NC
Will do, he bought that sensor from carquest. I also wonder if that Silverado TAC module burned something our because I had power on ground wires going to APP sensor when it was on the car, that's when I ran the numbers on that TAC module and discovered it did r belong on the Vette. I understand the TAC module has to be matched to the PCM. I can't help but this k I'm missing something simple. My first experience with a LS engine. Thank you for the reply.
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2025 Corvette of the Year Finalist - Unmodified
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I was looking up the definition for TAC and came across this site. Might be of use along the way…
https://easyautodiagnostics.com/gm/4...hrottle-body-1
https://easyautodiagnostics.com/gm/4...hrottle-body-1
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From: Supply, NC
Melting slicks
Hell Yeah, thanks a million. That article is on time, using a dmm. I don't have a fancy scanner, so hunting down this issue is challenging. Thank you for your reply, much appreciated.
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From: Supply, NC
Tps sensors center breaking
So when he got this car I started checking it out. Pulled the tps off throttle body and the plastic center where it slides onto the shaft was broken on the flat side. He bought a new one I installed it and this morning I pulled it off and the center of the new one is broken at the same spot. The center where the flat meets the rounded portion. They both look exactly the same as far as construction, looks like the plastic centers are weak to me.
I know I installed it correctly. Any of you guys run into this, what would cause this besides a cheaply made part. The shaft spins fine, it has some resistance because of the little electric motor. Thanks.
I know I installed it correctly. Any of you guys run into this, what would cause this besides a cheaply made part. The shaft spins fine, it has some resistance because of the little electric motor. Thanks.
