to start of this is my first thread on this site
i read a lot of posts and it seems like this is the place to be to get answers and i would like to thank you in advance for helping me
first off the only mods i have to my 03 wrx is a cold air intake, headers, uppipe, 3" catback exhaust, light weight flywheel and spec stage 2.5 clutch
now for the symtoms: rought idle not as smooth as when i first bought it and when it is cold out the idle goes high then low then high then low and eventualy coming back to normal idle speed. when i deaccellerate there is a raping noise (like when you put a baseball card on your bike and runs on the spokes) coming from the differentals. also had cel codes are po480 malfuction exists in the control circuit for cooling fan, po301, po302, po303 misfire in cyclinders 1,2, and 3. cel came on a week after i when into the ditch because of black ice and bald tires. when i got pulled out i let the rpms get to high and the rev limiter stoped it from going any further for about 2 sec. also my radiator/grill was packed with snow stoping any air flow through it. it never overheated though
any info on precaustions/reamidies i should do to improve the health of my wrx would be greatly apreaciated.