AK Subaru

Sorry I took so long to post back, but the problem is fixed! The computer was faulty. I replaced it and all codes are gone! Thanks for the replies.

Problem fixed. It was a wire that came out of it's connector under the dash.

I have a 1990 Legacy (manual transmission). The CEL comes on after about 5 minutes of driving. The abnormal voltage from the Speed Sensor (Code 33) is the only fault code showing up. The speedometer works just fine. The cruise control stopped working when the problem first started. Any ideals? Thanks!

The car runs great. Nothing out of the ordinary, other than the CEL coming on. Oh, there is one thing that I have failed to mention: When I had the black and green connectors connected, the engine cooling fans came on when I turned the key to the accessory position.

Yes - That is correct. It seems like they must all be real faullts, but I don't think so. I had thought that some of the abnormal sensor readings would have cleared. Especially the abnormal water temperature. The water temp is okay. I'm pretty certain all those sensors aren't bad either. We have had the car for 2 months and just recently started getting the intermittent CEL indications.

Your procedure for clearing the alarms from memory call for driving the car over 10 mph for one minute while the black and green connectors are connected. My trip around the block takes a bit longer than one minute. I get the "all clear" if I drive for just 2 minutes. If I continue driving for a couple minutes longer, the "all clear" 1/2 second flash changes to the alarm codes. So, I assume they are active alarms. With the connectors disconnected I get the intermittent CEL like I described in my first post. I also tried resetting the modules using your procedure that calls for disconnecting the negative terminal as well as removing fuse 14 for an hour or so. Thanks again!

Thanks for the replies Legacy777. I erased the codes... twice. The first time I initially got the all clear signal (steady flash at 1/2 second intervals), then started getting something else after about 3 or 4 minutes of driving. The second time I only drove for about 2 minutes and I got the all clear signal only. Then parked the car, turned it off and disconnected the green and black connectors. However, I am still getting all 6 trouble codes mentioned earlier when I connect the black connectors back up. What do you think?

OK - I finally got the car from my 16 year old son and a day off to read the codes. I had to let him drive my 2002 Tundra to school today though! Anyway, I connected the 2 ends of the black connectors using the chart and instructions from http://www.surrealmirage.com/subaru/subaru.html I have 6 codes cycling in this order: 33 - Abnormal reading from vehicle speed sensor 35 - Canister purge solenoid valve inoperative 12 - Abnormal reading from starter switch 21 - Abnormal reading from water temperature sensor 23 - Abnormal reading from air flow sensor 24 - Air control valve inoperative I believe these are historical problems that have occurred and been stored in the diagnostics system. My son had an overheat problem due to the radiator cap not being screwed on properly. And we found a connector on top of the engine, directly behind the air conditioner compressor disconnected. My question now is should I erase these codes and check them again? I believe I may have a truly faulty solenoid valve and/or air control valve, but that the other abnormal readings are just historically stored fault codes. Thanks for the help!

Thanks for the replies. I'll try reading the codes in the next few days and post my findings.

The check engine light on my recently acquired 90 Legacy lights up about 10 minutes after starting the vehicle. Sometimes it stays on, while at other times it goes out again. The car runs fine and everything seems normal. How can I troubleshoot this? Do I need a special tool to read diagnostic codes? Thanks for any suggestions.