Okay guys so my car has a persistent misfire under load at 4500 rpm or higher when im running 23+ psi. Anything under 23 psi the car runs fine. I am running out of ideas here so i will rely on you guys to help. Here’s the rundown on the car:
- built motor as of september 2022 (piston/rod/sleeve/crankhub). Will throw it out that the head has been refreshed by the shop also (new valve stem seals, machine work, & such). Car has frankenturbos, all the bolt ons, & all the fueling (twin 450 lpfp, reflex, 750cc injectors)
Here are the things ive tried to remedy this:
- New spark plugs ~600 miles old (ngk 97506 0.018 gap. Also tried 0.020 & 0.022)
- brand new eldor coil packs ~ 1000 miles ago
- i sent out the di injectors to get tested & cleaned while the motor was being built, all passed testing
- ppifpr injector bore fix kit (fantastic kit btw)
The car also keeps throwing a fuel mixture code. At this point i am considering doing o2’s, maybe cleaning the port injectors, & doing a leak down test to prepare myself for the possibility that there may be an issue with the head. What do you guys suggest?
important to note again that the misfire only happens when the car is making 23+ psi.
Here is a log: https://datazap.me/u/isslow/full-e8...d_qeJl08lbgs0O-pIcpFqMcK9of347nNd038Isl7adtUo
- built motor as of september 2022 (piston/rod/sleeve/crankhub). Will throw it out that the head has been refreshed by the shop also (new valve stem seals, machine work, & such). Car has frankenturbos, all the bolt ons, & all the fueling (twin 450 lpfp, reflex, 750cc injectors)
Here are the things ive tried to remedy this:
- New spark plugs ~600 miles old (ngk 97506 0.018 gap. Also tried 0.020 & 0.022)
- brand new eldor coil packs ~ 1000 miles ago
- i sent out the di injectors to get tested & cleaned while the motor was being built, all passed testing
- ppifpr injector bore fix kit (fantastic kit btw)
The car also keeps throwing a fuel mixture code. At this point i am considering doing o2’s, maybe cleaning the port injectors, & doing a leak down test to prepare myself for the possibility that there may be an issue with the head. What do you guys suggest?
important to note again that the misfire only happens when the car is making 23+ psi.
Here is a log: https://datazap.me/u/isslow/full-e8...d_qeJl08lbgs0O-pIcpFqMcK9of347nNd038Isl7adtUo