legacycentral bbs

Ive been driving my car alot for the last few months, and ive noticed that when im on the highway after about 5 minutes (Not railing on it at all) my check engine light will come on.

whn i get to where ever im going and shut my car off, the ligh doesn't come back on til i get back on the highway.

It doesn't make any sense, ive checked the codes and the only thing that blinks is the code for when nothing is wrong.

ive even reset the ecu, left the battery out over night, and it still does it.

So does anyone have any opinions?

Bad converter can do this or oxygen sensor probably both. I had the same issue a long time ago.

The cat in the midpipe is gone, so i guess i will look at my o2 sensor. thanks for your input.

These cars do not have a second O2 sensor. The chances of the cat causing the CEL are pretty slim.

I would tend to lean towards the canister purge solenoid. Depending on your driving around town, (non-highway) the canister purge solenoid may not be operating, or have the chance to operate fully and cause a code.

Trying connecting the green diagnostic connectors and do an "active" diagnostic to see if something comes up.

So should i connect the connector while the car is running or shut it off, because i have done it while the car is shut off then did the whole code check thing and i get 5 fast blinks consistantly

i think that's the code for everything is fine?

You need to connect the connector with the car off, turn the key to the ON position, but do not start the car.

The "all clear" flashing is a steady flashing light, no fast or slow blinks, just a continuous flashing.

The d-check mode is a little different. Instructions are on my site

www.surrealmirage.com/subaru/engine.html

It's probably flashing steadily then i haven't looked at the codes for a week or two now. but yeah ive turned off the ignition, connected the green plug, and turned the ignition on like you say and it does nothing but just blink. No codes.

It's weird how the light just comes on only when on the highway

You need to connect the BLACK plugs to pull the codes. The green plugs does not pull the codes. The green plug is the active diagnostic.

Ok i'll try that the next time it comes on. i guess ive been doing it wrong :\

You don;t need to wait for the light to come on. The car will store the code. So if you check now, it should have the code that was set last time the light came on.