Hey all, just bought a 97 Stagea RS Four a couple days ago. Just today, I started her up in the morning and noticed that the idle was a bit rough.
The car would idle, then drop to about 500 rpm, them go back up. I decided that letting the engine get fully warmed up before driving would be smart and after it did I noticed that under full throttle the car would get to 4500RPM, plateau, and then it felt like it "hit boost" and was able to get above that mark. Whats weird is after it "hit boost", there was an audible "pop" from I'm assuming the exhaust. Considering the car didn't have a problem when I bought it, I figured calling the previous owner would be a good idea. He told me that he had installed new spark plugs and a maf a couple months before I bought the car.
I know these RB25's love to hate their coil packs, but does what I explained sound like it could be that or maybe the wiring loom?