Broken Down S3

[Lightfoot]

Hi Guys,

After some advice, I have a 210bhp S3, mapped by angel tuning (although I think this is irrelevant, I was sitting at some traffic lights when the car started running on 3 cylinders, after about half a 500m I managed to pull over and saw the engine light was on. I turned the car off and tried to restart but it wouldnt start at all.

I have power as the engine will turn over but does not fire. Asuming it was electrical I had the car transported to my mates garage for diagnosis, he has tried his own scanner and 2 other from neighbouring garages but they dont pick up any faults.

I know coil packs are common on these but they have been replaced under warranty and surely all four would not go that quickly, would this bring an ECU light on?

Would VAG.com bring up something that these other scanners are not picking up?

My guy at the garage is convinced it would be a cam sensor or similar but I dont want to take the route of replacing parts to diagnose the fault!

Anyone else had this happen?

 

[S3 TAM]

It sounds like a coilpack issue but all 4 at the same time is not normal.
I thought coilpacks and cam sensors would show up on a scan. if there is a problem with them.
When my first coilpack went it did not show on a scan.

Sorry not much help but hope you get it sorted.

 

[Lightfoot]

Angel tuning said the same when I asked if the remap would make any difference to fault finding, my man at the garage is dubious due to the fact all four cylinders are not firing.

The guys have been using Snap on scanners (and similar) I was wondering if VAG.com would find anything that these other scanners wont?

Otherwise it looks like replacing parts to diagnose!

 

[S3 TAM]

I have a original VagCom cable and the coilpacks don't show on my scans when they have gone.

 

[Welly]

Hmmmm, my money would be on the Crank Speed Sensor.

They don't always throw codes. And would certainly explain the lack of firing from the engine.

All 4 coils at once? Na.

 

[Lightfoot]

Thanks Welly, my mate at the garage was thinking more along those lines, it did run on 3 until I turned it off and tried to restart but I still cant see the remaining 3 coils going just because the first one did.

 

[MIKE GTR]

Surely if the engine light is on its produced a code? - I'm not an expert i'm just summising

 

[Broken Byzan]

You have checked for a fuse gone havn't you?
Sometimes a coilpack blowing can blow the management fuse, failing that, Crank sensor is a common fail with no codes

 

[Welly]

Surely if the engine light is on its produced a code? - I'm not an expert i'm just summising

Nope, all the sensors on the 1.8T engines don't always gives fault codes under a failure condition. Which sucks frankly...

 

[Lightfoot]

Bit of an update on this, the garage are actually saying the scanner will not communicate with the ECU, would anyone have any idea why?

 

[Welly]

Bit of an update on this, the garage are actually saying the scanner will not communicate with the ECU, would anyone have any idea why?

Simple things like, they have got the ignition on?

 

[Lightfoot]

Yes correct procedures have been followed, we have had 3 guys look at the car. No one with VAG.com but I dont think this is the issue, their scanners have all said they should read an S3 but dont.

 

[scoobyra]

I had this problem with my A3 and Revo. It wouldn't talk to the ecu at all!

It is possible that a coil pack could've gone down or the timing has gone out. I stumbled across a fault on VAGCOM last saturday that said instrument cluster not sending signal to ecu (immobiliser!!). Get it on VAGCOM and see what it pulls up buddy.

 

[aragorn]

ECU fuse?

Post up your location, someone might be nearby with a vagcom cable that can have a look for you.

 

[Lightfoot]

I am in Bordon GU35

 

[Welly]

Also heard of a recent fault where the ECU had been ******** about with and wiring had been damaged.

 

[Lightfoot]

When you say ******** about with do you mean remapped or actually tampered with? I really dont think this has anything to do with Angel Tuning, they have done 3 cars of mine and this is the first to have a problem, it has also been mapped for a couple of months before it broke down. Its strange how it started running on 3 and drove fine (all be it on 3) until I managed to pull over and turn the car off. Then it wouldn't start at all.

If anyone close to my location has VAG.com I am happy to pay for some of their time, I am becoming a bit of a burden on my workmates catching lifts all the time!