-25% to -30% Fuel Trim at Idle, worried about CA SMOG
I am about at my wits' end...
A few weeks ago, I took all of my non-CARB compliant parts off and put my stock parts on to go get smogged here in the People's Republic of California. Well as soon as I did that, I started throwing misfire codes in cylinders 2 and 8. I swapped COPís and still had P0302 & P0308 codes. Swapped injectors, still had the same codes. I also noticed that my Long Term Fuel Trim was hitting -25% to -30% in Bank 2 during idle. Bank 1 was actually around -5%, so not too bad. Past 1200 RPMís LTFT was at ~1.00 or 0% so all good there.
Not knowing what to do, I did what any self-proclaimed YouTube Certified Mechanic would doÖ I cleaned out each fuel injector by spraying carb cleaner through it while pulsing it (connected it to the car battery) and changed the O-Rings and caps, then swapped them from one bank to the other. I swapped the COPís from one bank to the other, replaced the spark plugs, replaced the EGR valve, the IAC and cleaned out the PCV. What was interesting is the spark plugs in Bank 2 were pretty beat up. It looked like they had been through a lot of detonation. I donít remember feeling anything like that, but itís possible I just wasnít paying attention. Based on -30% fuel trim that would make sense I thinkÖ
I also found out I had an exhaust leak at the manifold to mid-pipe flange on the passenger side. Maybe this was letting O2 in and the sensors were getting false readings. So last night I crawled up there and made sure both passenger and drivers sides were mated up correctly with the gasket installed (thick edge facing towards the manifold flat side towards the mid-pipe). I also sprayed starter fluid all over my intake parts looking for a vacuum leak and couldnít find anything.
So where Iím at now:
No codesÖ YetÖ But Long Term Fuel Trim on BOTH banks is getting close to -20% at idle and Iím worried Iíll screw up my spark plugs again AND I wonít pass SOMG here in California. I also had this weird thing happen to me yesterday, where I let off the gas and put the car in neutral while coming to a red light and the car jumped to 3000 RPMís and would not drop. After about 30 seconds I turned the car off and back on, still at the red light and it reset itself. I really have no clue what to do next. Iím going to take it into the shop next week and have them take a look, unless someone here can help out with some ideas for me to try this weekend.
As always, all of the help on here is very much welcomed!