Irregular Check Engine Light

[Guest jetboy12]

I have a 94 Legacy wagon with a weird problem....Sometimes (not always) the check engine light comes on when the car is started. Doesn't affect engine performance but seems to happen after the car is warm. Any comments/suggestions ?

[Guest CROSSTBOLT]

Make sure gas cap is "ratchet clutch" tight & gasket in the cap is in good condition. I am assuming that the '94 is similar to the 2000 series of cars and a loose or leaky gas cap will turn that durn light on every time!

 

Karl

[Guest ferret]

94 was not OBDII (doesn't do fuel tank press/vac checks). I had a similar problem on my 90 legacy 2.2. After driving and stopping, the restart and drive away would turn on the Ck Eng light, then it would go off by itself. Turned out to be the O2 sensor.

[Guest jetboy12]

Thanks guys, was thinking O2 sensor but checked trouble codes (could only find green connections ?) and blinked a 01 meaning no trouble code. This ones tricky in that it only happens every once in a while and I can start and restart car and the light might go off. Also if I run it with the check engine light on, it stays on the whole time (doesn't seem to affect engine performance). Really got me confused ! Thanks Again !

[Guest Legacy777]

Have you read over the procedure on my site for trouble codes?

 

Try and find the black connectors. They are what you need to read the codes.

[Guest jetboy12]

Josh, Yeah I saw your site instructions (really helped !) and did the procedure for the green connectors. Couldn't find any black ones ? Does the '94 have them ? The green ones were right up front (unplugged). When I started up the engine (with the green connectors plugged in) and put it in drive the Check Engine light justed flashed for around a second so I assumed a 01 code ? Are the black connectors hard to find ? Should I take it to a dealer to read the codes ? Thanks for the help !

[Guest jetboy12]

Well went back out and found the black connectors (on the other side of ecu). I got 2 codes a 32 which is the 02 sensor and a 35 which is a canister purge solenoid valve. Which of these 2 would make the "Check Engine" light come on ? Are these easy to repair ? Know about the 02 sensor (do I need to replce it ?) but never heard of the canister purge solenoid valve ? Any help/tips would be appreciated !

[Guest Legacy777]

Both codes would cause the CEL go on.

 

What I'd suggest is clearing the codes. Either by connecting both black and green connectors and following procedure on my site. Or pull fuse 16 for 10 minutes. Drive the car. If CEL comes back on, check the codes again. See what codes are stored.

 

The canister purge valve deals with the emissions evaporative system. It can cause some poor idling problems, but overall it really won't hurt things too much.

 

If you get a code for both again, I'd look into replacing them. canister purge solenoid is under the passenger side intake manifold. If you follow the little vacuum line that comes off the top of the throttle body it will go to the solenoid valve.

[J-roo]

This light is also coming on occasionally in my 94 Subaru Legacy L. I brought it in for an oil change soon after and the guy said it was probably from 'the solenoid' and was involved with and only really important for emissions. I didn't get it fixed (a few weeks ago) and now my car won't start. It made an attempt at turning over at first, but the more I tried to jump start the car from my coleman portable battery-jumper thingy, the less sounded like it was starting over and the more it started just click-click-clicking. Is that clicking from the same solenoid that has to do with emissions? I tried cleaning the battery leads, but will do it again & a little better in the morning. I might also get a jump from a car battery. Any suggestions? I have read the posts on trying to connect different wires to different bits in the engine, but that is really no help to me as I don't know which part is which aside form the radiator, battery & dipstick. Oh wait, I'm the dipstick in there. Anyway!

 

Thanks!

[Setright]

The "canister purge solenoid" can give hard starting, but usually just rough running when cold.

 

It draws fumes from the fuel tank into a charcoal canister. From here the solenoid valve is supposed to let the fumes into the engine when it's warm. If it feeds the fumes to a cold engine the mixture gets over rich and causes problems. Not least if it creates to great a vacuum in the fuel tank, since that makes life hard for the fuel pump!

 

Start by replacing the solenoid, disconnect the battery for at least 30 mins to reset the CEL.

[Olnick]

The "click-click-clicking" you're hearing could be the copper contacts in the starter. They pit and wear away over the years and eventually won't make enough contact to feed electricity to the starter motor. They can be replaced--new contacts are realtively inexpensive--but you have to remove the starter to get to them. It's not as difficult as it sounds!

 

There have been write-ups about it here on the board. A search should turn up a lot of information. And if you need help, just ask! Good luck.