Hesitation and Misfire after 4K RPM Under Boost
 

2018 Toyota 86

Parts:
- SBD G500x Turbo Kit
- Mishimoto Oil Cooler
- MXP Comp RS Exhaust

I recently just got my car back this month after getting into a minor fender bender. After I got it back, I went for a drive and tried to do a WOT, but it started hesitating and stuttering after 4K RPM. The CEL would start flashing. On idle, the car runs smoothly and has no issues. When I drive normally under 4K RPM, there are no hesitation issues at all. The body shop told me they didn't touch the engine or drive it anywhere except for to the paint shop, so I don't think they could have done anything. Before the accident, I was driving the car perfectly fine though, no issues. I guess sitting in a body shop for a month may have caused this issue? I'm not sure...

I took the car to my mechanic and they told me they noticed the hesitation issue and suggested that I may need to upgrade my fuel pump and fuel injectors to compensate for more air coming into the car. My mechanic did a compression test in cylinder #2 and they did not find low compression. Marin from Marin Tuned told me that my car was getting plenty of fuel and that upgrading my fuel injectors/pump was not necessary.

I talked to my tuner (James from HRI) and the only thing he has suggested so far is to diagnose if it is a coil pack, and replace the spark plugs.

I plugged my ECUTEK into my car and got the P0302 code.

1) I swapped out the old spark plugs with new OEM spark plugs on all 4 cylinders

2) I checked to see if it was a coil pack issue by switching coil pack #2 with coil pack #4, but it still showed the same misfire on cylinder #2

3) I checked to see if it was a fuel injector issue by switching the fuel injectors on the rail on the driver's side of the car, but it still showed the same misfire on cylinder #2

4) I checked if any hoses popped out or for any leaks

I have considered that the DI seals may potentially be the issue, but I am not experiencing any popping noises when I drive. Maybe the wiring for the port injector is faulty? I am running out of solutions and don't know what to do anymore. I don't think it's clutch slip either because once I go WOT past 4K RPM, it goes up very slowly.


Does anyone know how I can fix this or if anyone knows places in Southern California that could help me out with this?

It would be much appreciated!

https://datazap.me/u/jpcrayola/log-1611729147

P0302 if accompanied by actual power loss and felt missfires (you can hear the engine sputtering and struggling to rev) are actual missfires and not something else (like clutch slipping or anything elsewhere in the driveline). Missfires are actually quite simple, you need spark, fuel and compression to be right to not have any. You said you changed the sparkplugs by new ones, so those are out. You swapped port injectors and coilpacks around and issue still pops on cylinder 2. So only 2 more things to check remain. Your direct injector in cylinder 2 is having problems (injector itself, seal, or both), or your compression is out of whack on cylinder 2 (headgasket, or something in the cylinder or piston). Start by taking both injectors out of that side and compare them, if they look normal swap them like you did port injectors and see if its still there. If its still missfire you have a deeper problem that may require you to actually open up the engine. Usually this is not the case on FA20s, but you are boosted so Im leaning on your head gasket or compression being out of whack from an internal damaged, but I hope im wrong and its just an injector seal.

Is it possible that your car was low on gas and they filled it with low octane?
Should show up as knock, but who knows..

check grounds, specially on the DI ECU near fuse box

yeah, i think DI seals might be the case. im taking it to HG performance next tuesday to get it fixed.