hey guys I'm posting a thread here because I cant seem to get my car to idle I've tried many times to no avail I've done many different things.A list of some of these things including checking for vacuum leaks making sure I have good spark I've checked for exhaust leaks I've replaced the MAF sensor and o2 sensor with known good ones my car is pulling lots of fuel and It will idle if I unplug the maf or o2 sensor it is in closed loop fault most of the time. I believe this is to do with the fact that I have a p0038 I am not sure why because I've replaced the sensor with a known good one and it seems like I might have a wiring issue somewhere. the car idle better after all ive done but now when I refilled I tried 87 octane and I now have 0 idle and the car stutters at 4,000 rpm when I go to full throttle this only happens when I put 87 the car is pulling 18-20% of fuel from the LTFT and I am not sure why the car is pulling a low amount of air at idle around 4.7g/s. I've been told this is normal but the car seems to be misfiring on cold start the engine light is not flashing but I cant tell that it is my friends rx8 doesn't do this. when I installed my engine I broke off the little grey piece of the apv do you think that this could be the cause of all of this? I have good compression tested 115 and 105 if you can please help me figure out this issue.

 

Bad harness it seems like its not anything physical but more electrical, try replacing the harness.

 

Alright I'll try that I've already replaced the harness once when I put the engine in because of a short but I'll try again the harness I put in is probably not good it was the one from the old engine I can take the harness from my old engine which is know good