Check Engine Light

I have a catback exhaust on my 02 WRX and I believe the exhaust is after any o2 sensors. The CEL came on during a long drive from Milwaukee to Minneapolis and hasn't gone out in the last couple days. Would a cat back cause a CEL? I feel like you could fart and cause a CEL with these cars.

Am I at the mercy of the dealer to get the light checked/reset or is there a way to pull the codes by pumping the gas or brake etc. like on OBD1 cars? Do generic code readers work?

Also, is there a good factory manual out there? I like to do my own work.

Thanks!

 

I have yet to see a CEL in a Subaru, and we have 3 here at my house. I would get it scanned and see what it is. If its still running good, I would guess it is an O2 sensor or like a fuel code from leaving the gas cap off. I don't know of any techniques for clearing codes other than with a scanner.

 

Step 1: Go to any local Autozone. Ask a guy at the desk to scan your code, he'll bring a reader out to the parking lot, hook it up to your OBDII port, and give you the code. Then come back here and let us know which one it is.

Step 2: To clear the code (the Autozone guy might or might not do it, technically they are not supposed to but some will), you can reset your ECU. Disconnect the negative battery terminal. Stand on the brake until the juice is out of the system, or just leave it disconnected for about 15 minutes. Reconnect and your CEL should be off and the code should be cleared. It will also probably turn itself off after about 8 cold starts (but will retain the code).

 

I may have disconnected mine as I got sick of looking at it.

 

if you are down the shakopee area drop by the store and I could pull the code for ya and double check it isnt anything to worry about... I fill my WRX up with engine running all the time adn never has it popped a code... so the gas cap may not be a problem unless you drove with it off or too loose,

Make sure I am here at the store if you decide to come by... Nathan..
952 224 6353

 

Thanks for the suggestion Zola. The codes did not go out after a week.

I stopped into AZ today and they read the codes and then cleared them.

It pulled a:
P0301
P0303
P0304

The code reader said they were cylinder misfires on 1,3, and 4 cyclinders. Coil related?

I drove it home and no new code was tripped. Advice?

Thanks

 

how are the plugs, gas? I pulled that code this week, but mine was all due to Launch Control }.

 

Pretty common on WRX's that have an underdrive pully and/or lighweight flywheel. If you have one/both, keep an eye on the codes, but as long as you generally get all 4 cylinders giving lights, there's little to worry about. Also pay attention as to when the light is coming on(slow speeds, from lights, high loads, whatever).

If your car does not have those mods, look to #2 cylinder(it's one of the rear ones, someone will have to remind me which side). #2 and #4 have a tendancy for problems as they may not get enough cooling and/or enough gas, but don't generally give problems in unmodified cars. You never know...

If the car's running good/feeling strong, I wouldn't worry too much about it. But do keep an eye on it.