Audi TT Engine Management Warning Light

00sully

just noticed its on now - anyone now what the possible causes could be? Or what I am likely facing?

it seems to drive fine??

Neilw

I'd say your best bet is to post a question here http://www.tt-forum.co.uk/

Neil.

crosstownk

It could be one of numerous faults. The EML comes on for a variety of reasons and it's impossible to make a stab at it over the internet as your car is not displaying any other symptoms. It could be just a momentary fault whereby the fault memory will simply need to be erased, or it could be something that needs repairing or replacing. For peace of mind it's probably best if you at least get a diagnosis. Those cold winter nights are on the way and Murphy's Law says that it will bring the car stop on the worst day possible..............

00sully

thanks neill, some good topics on it on there!

yeah crosstownk, think ill get it checked out alright, just hope i dont get shafted cuz i know feck all about cars :-/

lomb

the fault will be erased from memory if the battery is disconnected for an hour and reconnected .id do that first before doing anything. if it reappears then it will need to be diagnosed. make sure the petorl tank cap is tight, and also consider replacing the spark plugs if they are old as they load the ignition coil. ignition coils are common failures on vag cars. chances are it is a failing coil if it relights. these are easy to change if you can change the spark plugs.

00sully

top tip lomb! thanks mate

I also just purchased a VAG-COM cable to run a diagnostic on the car to see what error codes I get before I take it to an authorised dealer which will cost €€€ just to look at it.

Ill disconnect the battery later so, thanks for the tip!

sul.

~~SKYHIGH~~

EMS lights can come on for silly reasons.... Dealers charge a lump of gold to just plug it in to a diagnostic socket.

lomb

no prob, here is another tip, do diagnose which coil it is if the engine is running rough just remove the plastic engine cover and pop the fuel injectection wire to each cylinder and listen to the engine note. it will sound rougher for all the cylinders except the one that has failed. you can drive safely on 3 cylinders providing you remove the fuel injection wire to the failed cylinder. this will protect the catalyst from unbunt fuel. coils can be had on ebay or gsf for about 30euro

yop

ARe u a mechanic Lomb, u fairly know your stuff

craichoe

yop wrote:

ARe u a mechanic Lomb, u fairly know your stuff

Erra thats pretty standard stuff, if you remove the cable and it makes no difference then it means the plug is dead.

yop

Im on about his coil diagnosis

00sully

:eek:

this is getting a bit much, im skeptical even disconnecting the battery - im a tech head who works in IT but know sh*t all about cars/engines!

I still haven't disconnected the battery. how should i proceed? will it blank the cars memory? i.e. radio codes etc? the car has a stock radio. will I have to get my keys recoded?

fair play lomb, but errr I dont think i'd be confident diagnosing coils and cylinders or what they even look like

crosstownk

lomb wrote:

no prob, here is another tip, do diagnose which coil it is if the engine is running rough just remove the plastic engine cover and pop the fuel injectection wire to each cylinder and listen to the engine note. it will sound rougher for all the cylinders except the one that has failed. you can drive safely on 3 cylinders providing you remove the fuel injection wire to the failed cylinder. this will protect the catalyst from unbunt fuel. coils can be had on ebay or gsf for about 30euro

This will introduce more faults into the fault memory. The OP's car is displaying no physical symptoms.

OP: You say you bought a VAG COM cable - why not plug it in and see what faults are displayed? Anything you are reading on this thread is pure guesswork - your fault light is on yet your car is displaying no symptoms. It is impossible to diagnose over the internet. Pulling wires off here and there with the engine running will add more faults to the fault memory and lead to confusion if you do bring to a dealer/mechanic for repair.

00sully

you are probably correct. I think i will wait until my VAG COM arrives (ordered it Tuesday, shipped yesterday from England) hopefully will have it soon.

Just hope nothing happens in the meantime!

thanks all for advice - I think its time I started to learn more(anything) about cars :cool:

lomb

no im a dentist who likes tinkering with cars. i repaired my own golf(failed coil on cyliinder 1) and fathers corolla this way(that was a dodgy denso). all the information is on uk-mkivs.com. disconnecting battery is the standard way on vag cars to erase the ecu. it even says so in volkswagen manual in the glove box. i can get you the page number if no one believes me. the correct procedure according to manual is to disconnect positive wire, then reconnect after 1 hour, turn ignition on but dont start car, leave on for 30 seconds for throttle to reset, turn ignition off without starting, then restart car and drive normally for 10 minutes without idling the car all the time. this reset ecu back to base, and the 10minutes of driving reprogrames it. it also clears the faults. i changed the coil on my golf and the fault light remained on, doing the ecu reset above cleared the light and it has stayed off since.
teh ecu can also be cleared via vag.com.

kvw

chech that your rear brake lights are working Sully.

seriously.

crosstownk

kvw wrote:

chech that your rear brake lights are working Sully.

seriously.

Damn right - I forgot about that. And if they are working, check that you have the correct bulbs fitted. Wrong/blown brake light bulbs can, sometimes, bring on the EML.

Neilw

Coil packs are a known problem on the 1.8t engine, had one die on my leon...car had no power and ran like a bag of spanners with one dead coil pack.

I replaced all 4 as usually if one goes another will follow not long after :mad:
I now keep a spare in the boot along with tools to fit it!

Neil.

lomb

00sully wrote:

:eek:

this is getting a bit much, im skeptical even disconnecting the battery - im a tech head who works in IT but know sh*t all about cars/engines!

I still haven't disconnected the battery. how should i proceed? will it blank the cars memory? i.e. radio codes etc? the car has a stock radio. will I have to get my keys recoded?

fair play lomb, but errr I dont think i'd be confident diagnosing coils and cylinders or what they even look like

stock radios have a chip in them tying them to engine management so that you wont need a code as long as it is not put in another car. keys wont need to be recoded either.

lomb

Neilw wrote:

Coil packs are a known problem on the 1.8t engine, had one die on my leon...car had no power and ran like a bag of spanners with one dead coil pack.

I replaced all 4 as usually if one goes another will follow not long after :mad:
I now keep a spare in the boot along with tools to fit it!

Neil.

i think its the worn spark plugs that load the coils. mine at 45k miles were quite badly worn. should have replaced at 40k or probably earlier. i have just replaced one and the plugs hopefully no more will die;)