Random check engine light
 

I'm getting the Check Engine light at random intervals but its not storing a code. The previous owner said the same thing but said it was checked twice and nothing registers. He was advised it could be a sensor going faulty but i'm not sure. The car drives ok wether its on or off.

Drove it the other day, came on for 2 seconds, went off, came on again 50 yards later then went off and didnt come on again.

Tonight I got in it and it came on as soon as I started it, then went out after 10 seconds and didnt come back. Its got me stumped, but worried too.

also, how quick should the car take to warm up? mine is a my00 classic and it seems to warm up pretty quick, under 5 minutes, is that normal?

the boxer engines are about the fastest engine available to warm up so I wouldnt worry too much about that.

Could be a slight possibility that the knock sensor 22 is faulty or getting that way, seen those fail quite frequently, you could really do with someone with a subaru code reader pluging into the obd socket just to find out

The previous owner said he took it to Subaru twice when it started happening but no codes stored. If the knock sensor goes, what are the symptoms?

Check light illuminated, or the occasional flash while driving the car.

just occasional flash while driving, but today is the 1st time its come on when starting the car. Sometimes it comes on so fast you barely see it.

what will it run like with a faulty knock sensor?

i think it'll cut the boost to 0.5 when it detects knock.

the knock sensor has gone on my MY95, i've had the sensor off and its cracked, i'm just waiting for the new one to come.

have you felt it down on power at all?

nope, no difference in performance at all, but the light doesnt really stay on long enough to affect it.

If anyone has a spare sensor laying around can they let me know so I can try it and rule it out as a possibility. Cheers

Can't help with the cel issue :( maybe check all your connections to the sensors? Or do a full ecu reset using the plugs under the dash (scoobypedia for that info).
Now warming up the car, you mean the water temp? That will warm up pretty quickly, your oil temp takes a fair bit longer and unless you have a set of gauges, give it 5-10 miles or it won't be up to operating temperature.

Tony:)

you will need to get the numbers off your sensor as the are quite a few different types.

Seems like the CEL stays on more from start-up now. I was in town tonight and it stayed on for the 1st 2 minutes of driving then went off. After a couple more minutes driving I have to come up a steep hill to my house, and it came on again.

I'm hoping its stored a code so I can sort it, but i'm wondering if its something oil related? While the light was on I put my foot down and it doesnt appear to affect performance so i'm a bit stuck til it stays on.

Does your car have the stock ECU? Maybe for some obscure reason your ECU cannot store codes? Try starting the car with the MAF or TPS sensor disconnected. Then check for codes. If you don't see any codes then you have an issue and can't store or read codes - never heard of this happening but I guess it's a possibility.

If you get a code from the above then it's likely a short of some kind on the wiring for the CEL.