CEL extremely hot day

[ODB]

Hi team,

hoping someone can shed some light here.

99 forester STB.

Took my little boy to the beach for the first time on the 3rd.

Was a blazing hot day prob 32 degrees outside.

Had aircon on for the 40 min drive each way. Just before getting home went up an on ramp and hit 100km/h and had the CEL come on...first time ever for me.

Driving didnt seem to be affected in any way and didnt hear any noticeable pinging with windows down at next lights.

Mrs had filled up at shell that week she advised me (so 95).

Turned car off and restarted. No check light.

Left bonnet up and topped up coolant slightly but havent had a repeat since.

Im thinking just with the aircon on for ages and a really hot day might have had some slight over heating or possibly a little pinking (altho i didnt think so as it didnt go into limp mode at all).

Cheers

[Guest S T E Y E]

have u checked for loged faults??

i got a similar story..

i was driving from auckland to rotorua the other day and i was just sitting on 100kph constant and my CEL came up... i turned it off and restarted and fault went out... when i got to rotorua i cleaned my MAF and cleaned all the plugs cpnecting all the sensors (had a bit of oil/dirt etc in plugs) ..

actually to think of it i havent checked faults ill do that today and see if it logd one...

but my theory was that the dirt/oil in the contacts of the plugs added resistance and made 1 of the sensors go out of the voltage range the ecu likes to see... so the cel comes up...cos after cleaning all conectors mine has never done it since and ive driven it heaps...

something u could try is clean the conectors bro and check faults...ill do mine soon haha fully forgot

[ODB]

dont think its that.

i am more of the mind the constant A/C use and hot as day with lots of city driving drove temp up to a high level thus CEL came on.

But i will check the MAF etc for grime build up.

[Guest S T E Y E]

was ur gauge overheating???? dont think it actually throws a cel wen it overheating...may be wrong tho?? my mates would overheat to nearly top of gauge and no cel

[zarnah]

amys wrx always throws cel's and never has a code stored, live with it haha

[Guest S T E Y E]

well wen it does that i reckon its the conection in the plugs bro...giving high resistance and or open circuit for a split second...like i said i cleaned the conections and never done it since...u should try it and see if it still faults