I recently swapped out my vq non rev due to a spun rod bearing. The engine I installed is out of a newer model g35 with a different type ecm and single plug tranny. The place I bought the new(er) engine from cut all of the connector plugs off of the wiring harness, so I opted to use the old tranny (3 plug) and old harness (along with other components from the old engine that still worked). Everything hooked up just fine and the engine started right up, the problem was that it went into limp mode and I cannot for the life of me get the tps to re learn anything. I used an obd2 reader to scan the codes and its sending a p0226 code. P0226 2003 INFINITI G35 - Throttle/Petal Position Sensor/Switch 'C' Circuit Range/Performance Problem. Has anyone else had this problem when swapping engines?

 

Did you try to do a idle air volume, acc pedal position, and throttle valve closed resets?
Timing is crucial and engine up to operating temperature

 

As long as it was another VQ35DE (not the rev-up with the extra exhaust solenoids and cam phase sensors) from a G35, 350Z, M35, or FX35 then it's fine. The rev-up version won't work properly out of the box though but you would have extra harness connectors on the motor that were unused so you would know if it was a rev-up motor.

That code is for the GAS PEDAL, probably unrelated to your engine swap unless you were doing something to the gas pedal switch.

 

I did attempt to perform the resets you mentioned with a stopwatch in hand. No luck. I couldn't even clear the ecm, almost like it's not receiving a signal at all fro the accelerator. As far as the engine itself. The new(er) engine was verified as a non rev. I haven't performed any work on the accelerator sensor. Just the engine wire harness. I'm at a loss... am I going to have to limp the car to a dealer to have them reflash the parameters?

 

So I figured I would post what I did to fix the problem. I started the car and checked to see that it was still in limp mode as I hadn't started it for nearly a week. It remained in limp mode. So I started experimenting by unplugging sensors while it was running. When I got to the throttle body I unplugged it and it almost died, but caught itself and was idling lower. I plugged it back in and shut the car off. I switched the car on and tried the ecm reset procedure and it worked first time. All codes cleared and running like a champ again. Prior to this working I had tried the ecm reset many times with no luck, almost like the TB wasn't receiving a signal from the accelerator. Anyhow just thought I would leave this here in case anyone stumbles onto the same symptoms I had after the motor swap.

 

That's wierd, must have been something contaminating the electrical connection or maybe a little corrosion on the TB pins if it came from the donor motor and simply unplugging it scraped a little corrosion off.

It would probably be a good idea to disconnect the ba5tery, the TB harness, then spray some electrical contact cleaner on the pins or the problem might pop up again.

 

Yeah it didn't make sense to me either. The TB is the one off of the bad engine and it was working fine when I swapped engines. It was almost the equivalent to "did you try turning it off and back on?" Whatever the case, I'll take it. Good advice on the contact cleaner.