2.0 8v not starting

[ARB1991]

I bought my MK3 4 days ago and its already let me down on the way home from work I drove through a fairly shallow puddle as I arrived at work and it started misfiring badly as I pulled up. I left it running for a minute and gave it a few blips on the throttle and it seemed to misfire when the throttle was over about 75% open. I left it for the day (had to start work) and when I came back to it it started up straight away and seemed ok but when I pulled away from the car park it died. Had real trouble keeping it started in traffic and managed to get to a layby. It seemed ok when i eased the throttle on and happily revved to around 5000rpm but as soon as i let off and planted my foot again it missed and died and hasn't started again since. I've cleaned the throttle body out and checked the coil for a spark, took the dizzy cap off and that all seems ok, oil is a bit low but would that cause it not to start?

Any help would be greatly appreciated

[itavaltalainen]

what engine do you have (engine code)?

sounds like ignition problem though, but since you checked could be other things but there are 3 different 2.0 8v engines in the mk3...

[ARB1991]

I'll check tomorrow

[madmanmart]

My guess is HT leads or coil on its way out

[matty james]

does the throttle body not re-set by vag-com after cleaned

[itavaltalainen]

depends on what engine he's got....

2E does not need to be reset (it's a pretty dumb one  )

[ARB1991]

engine code is  AGG 174 898. Battery now dead from turning over so much :/

[itavaltalainen]

check the ht coil for hair line cracks (also check ht leads and dizzy cap with a spray bottle)

check crank sensor and its wiring

re-adapt throttle with vcds (disconnecting battery will not do it and it also does not teach itself like other engines)

[boneybradley]

as said check the coil, leads etc by giving them a dose of wd40 or similar and see when it improves (if it does)

(I'd bank on coil myself but knowing these engines! b.t.w I keep them stock £21 delivered for the agg)

[VW BUSH]

as said check the coil, leads etc by giving them a dose of wd40 or similar and see when it improves (if it does)

(I'd bank on coil myself but knowing these engines! b.t.w I keep them stock £21 delivered for the agg)

Dont ever spray WD40 on suspect leads, coil or ignition especially when the engine is running.
It catches fire trust me.
Use water in a spray bottle and look for it arcing, if it sparks then fit new parts.

If you must use it then wipe up excess and do it on a cold engine.


I would go for coil as being suspect, I always fit new leads with a coil as leads with high resistance/damage cause the coil to heat up internally.
Crank sensor next.
Itavaltalainen is right about the ADY TB it needs a proper Vag com re set if out.