We have a 2000 Civic ex with D16Y8 SOHC VTEC. We bought it back from the guy we sold it to. He had aftermarket catback exhaust on it and we put it back to just regular like OEM. I think when trying to pull the rubber for the O2 sensor through the hole I pulled too hard on some wires that ended up being for TPS. (I think that's what happened, I was fighting with a lot of stuff under the car at the time) We replaced the TPS after and changed the plug. Ended up accidentally wiring a MAP sensor pigtail for the TPS but dad is a pretty good electrician and figured out which wire will be correct. (Still not 100% if using MAP pigtail is okay?)

First changed out TPS. Got P0122 code. He had used a pigtail before and just had it hooked up with butt connectors. Then soldered in the MAP sensor pigtail. Code still there. Car is acting up all over the place. Sometimes it struggles to get past 20 mph with almost pedal to metal. Getting up to 3k (?) rpms or higher before shifting to 2nd. (Automatic non CVT) Sometimes it's drives kinda normal. Sometimes it slams from 2nd to 1st on letting it coast. Dad has done most of the testing from FSM. He swears he can't do the test of checking the TPS voltage with scanner. We have the Blue Driver scan tool and I think that he could do the test with Absolute Throttle Position live data (percentage) but he says it's not the right data. There is no TPS voltage option on app?

He checked at the ECU and says it's not the ECU that most likely there is a short in the wire somewhere. We don't know where all the connectors are so we can do the next tests.

Any suggestions on what to do next?? He's getting pretty frustrated. I will try to answer more questions but I haven't been around for the entire process. Thanks in advance.

 

so you have verified 5V and GND on the right pins at the TPS connector? back-probed the signal wire (i think C27, TPS) at the ECU to verify the range is in tolerance?

If the scanner won't do it for whatever reason, a multi-meter will. it just takes a little more effort.

I would have a close look at the wires and recent repairs to the wires to rule out any possibility of a short to ground or weak (high resistance) connection. open the loom if you need to so you can trace the wire all the way back to the ECU.

if all the wires check out, maybe substitute a known, good throttle body.

 

Sorry for taking so long to reply. He did more poking around and apparently he wasn't installing the actual TPS correctly? He said something about how the notch was and he thought it was supposed to go one way but it was wrong. So that fixed that code. Now we are intermittently getting P0505. The car got the engine replaced and the mechanics had replaced the IACV but I know the idle was all kinds of crazy after and they adjusted it and it was better. Maybe more idle adjustments again? Thanks again.