My "Service Engine Soon" light keeps coming on and off. It will come on and stay on fit maybe 30-40 miles, then it turns off again for a while. I haven't really noticed a pattern to it. I had one of my buddies hook up his computer, and it wad giving me a fault code for the engine running too lean. I have an Agency short ram air intake on it. I cleaned my MAF sensor and it went away for a but, but more it is happening again. Is this a common problem? Perhaps you guys know of a quick fix?

 

Quick fix? Remove intake, replace with stock. The less quick option is have the car tuned or at least re-scale the MAF for the larger intake (also requires reflashing the ECU).

 

O2 sensor

 

I don't think the car will give you a code for anything except the rear O2 sensor reading lean indicating that there is probably an exhaust leak between the front and rear O2 sensors.


Edit: the reason I believe this is I've had friends with wideband that were running FULL lean with no CEL, though I got a rear O2 sensor lean reading when I had an exhaust leak between my downpipe and testpipe.

 

post the code if you can.

 

i had same problem. it might be loose vaccum line. I bought new hose and light went away

 

Old thread, but yeah, this is incorrect. Installing an aftermarket intake without re-scaling the MAF will result in you running lean. The OP is reporting an SES light, not a reading from an AFR gauge. Code is P0171, if I recall correctly.