[Audi A3/S3] s3 engine management light on.

[ants3]

G'day everyone. Looking for some help please? I have an audi s3 2001 and the enginemanagement light is on for some reason. I recently changed the thermostat and it popped up after that. I have cleared it,battery disconected,that old chestnut. Fine for a day and half then back on. Bit reluctant to use it to often now incase of any damage I might be causing. I've checked everything that I might have come into contact with while changing stat but everything looks a-ok. I've checked it out on vag com and its come up with naff all. Car seems to run as normal,tried clearing it again,came back on next day. Doesnt seem to come on when engine is on,just when turned off and back on again. Any ideas fellas? And yes,I've already cleaned out the carb,overhauled the flux capacitor and the hyper drive system drive belt was changed couple of months ago. If you got any ideas it would be greatly appreciated. Thank you.

[PetrolDave]

What fault code is stored when you look using VAG-COM?

That will give a good clue what the cause is, and whether it's a minor fault (which means you can drive the car without a problem) or something more serious.

[BW2309]

On any 1.8T the main causes for an EML (without running issues) are a duff coolant temp sensor or ingress of un-metered air. A check with VagCOM will show either a simple fault that is self explanatory but id it suggests that the car has been running too lean or has general fuelling faults then a leak on the breather system is highly likely. There are a few rubber breather pipes on the bottom of the inlet manifold and the cam cover that can deteriorate and allow in air.

There is also a non return valve in the system called the PCV (positive crankcase ventilation) valve. If this failes the engine can continuously draw air from the crankcase and so this effects the fuelling as it's not being measured by the air mass meter.

Most failures regarding coil packs etc should be accompanied by a fairly severe missfire!

Hope this helps...

[ants3]

Fella's, replys most appreciated. I've got nothing coming up on vag com. Doesnt run any different as I can tell. Will check for leaks in the hoses and go from there. It does seem weird though as I've recently, I mean a couple of days before light came on, replaced the thermostat. It does, in a strange sort of way, tie up to the temp sensor. Does this sound silly or feisable?? Cant work out why vag com aint picking it up? Dont tell me its got this sodding swine flu? I've tried saying comforting words, everything is gonna be alright that sort of thing but not tried any beechams or oat yet.

Thanks for your time and help. Great site. Very helpful. Cheers:-)

[Paul]

Did you change the thermostat ( ie mechanical device)

or the temp sensor ( electrical sensor)

Your last post mentions both.

If it was the temp sensor, was it an OEM Audi part (usually green bodied, to replace the black type that was fitted) or equivalent aftermarket part?

Did you plug everything back in when you changed the sensor?

I know i have forgotten to plug in the MAF in the past when i have had the airbox apart to fit a filter.

[ants3]

Hello fellas, sorry bout delay but got alot going on at moment. Anyway,thanks again for your help. I have checked the pipes round engine and I really cant see anything obvious, all looks a-ok. Light came on after I changed the thermostat which does make me think it could be sensor. By the way, anyone doing their own thermostat change, make sure you have an abundance of sockets, extentions, knuckle joints, new dip stick tube, fresh packet of fags, a book of new swear words of the 20th century and get hold of that bloke that lives at the end of the street that tells you that you are doin it all wrong! Even though the last time he worked on a car it had a starter handle on the front. Anyway......Yeah, sorry, where was I. Theses temp sensors, gotta see if its a black one. If it is replace with green one yeah? Also, how critical are they on engine numbers? Mines AMK, found write up on BAM temp change and states only BAM?? Last one, there is one on ebay. 4pin, green, right year but dont list engine code. Would try me local audi garage but 2be fair, they seem a bit....well dim. Apparently the dip stick tube I had in my hand wasn't the one off my car. I must have dropped it and picked up one on the floor that was off another car. Amazing. What was the odds of that hey? Anyway, it is the right car, engine, tube. Guess bloke down street has a brother and he works at audi. Tw@t!(By the way, luv that word. So discriptive, can be said with so much conviction and just rolls of the tounge)

Right, thats it. gonna have another beer. Cheers everyone:-)