Rough idle, now doesn't start properly

[AcidUK]

Last night on my way home I noticed that when waiting at junctions/lights, my 2001 1.4L petrol golf seemed to shake subtly every few seconds. I popped the bonnet when I got home, and the engine was doing a good tractor impression. I also noticed that it was really shaking around on top of the mounts, shaking the whole car. There was a small black box with a pipe exiting from it, between the washer and coolant resevoirs, I'm not sure of its function, but I noticed it was clicking quite loudly.

Fast forward to this morning, and my dad had tried the car in the morning, and apparently it started and idled fine. I just hopped in to go pick someone up from the station, and the car wouldnt start. The starter motor (not too long ago replaced), was struggling to get the car going. I stopped trying, and left the car for a few minutes. When I came back, I managed to get the car to start by holding the ignition and really pumping the accelerator. After spluttering a few times, it just about "started". The car was shaking a fair bit, and the revs were dropping well below normal idling levels. Very quickly the ECU light came on, and I turned the car off.

The car has a poor service history. It has had regular oil + oil filter (+ ?fuel filter) changes, but not much else. Its a 2001 with 45k miles on the clock. It is driven reasonably heavily, and had done quite a big trip 2 days previously.

I'm relatively unknowledgeable about cars, but my dad is a trained engineer, and any advice you could offer beyond taking it to the garage (I'd really like it running for Christmas), would be greatly appreciated.

Cheers,
Seán

[goldenoldie]

heres 2 things u can check 4 free as it sounds like air leak between air filter and throttle body(bit that connects air pipe 2 engine) check this pipe 4 cracks/splits... replace as nessasery.. leads to mucky throttle body butterfly which cuts the engine at idle and rough idle/ hard to start.

With this pipe off ..look inside hole where it connected to engine. U see a circular valve. this valve(butterfly) need to be as clean as glass. if not ,VERY DELICATELY clean with carb cleaner.

personally i would get a machanic to clean throttle body as some need calibrating to idle correctly. hope this helps.:Blush:

[AcidUK]

Thanks for the advice goldenoldie.

I took the car to a garage to get the ECU codes checked/cleared.

There were two codes:
P1570 Engine ECU Blocked - Intermittant (This one cleared)
P1444 Potometer for EGR-G212 Not a Plausible Signal (Would not clear properly) The proper error code for this is: EGR Valve Position Sensor Range/Performance

The light went off for one start, and then came back the next time it was started.


The car starts and drives normally, but the idles when warm mightbe slightly bumpy. I suspect then that my EGR sensor is done-for. I have tried disconnecting the battery to clear the fault a few times, and it simply returns on the second start of the engine. I have disconnected the multi-connector to the EGR to see if I could hear any difference (to see whether the EGR is actually working) - but I couldn't.

I don't know whether to just bite the bullet and buy a new EGR for £114. I don't know for sure that this is the problem, or that replacing it will solve this issue. If the code could not be cleared by the vagcom, does that mean that its a firmware issue?

Does anyone have any advice? I've ordered a vagcom cable, but its from hong kong, and won't be here for a while.

All input would be greatly appreciated.

[andrew_jmdata]

Hi - Am afraid I am no mechanic or car expert in any way... however... I have had similar / same probs with my Golf (and Renault Scenic) and on all the occasions it was faulty ignition coils. This is a known problem with VW's and Renaults and RAC patrols carry stocks of these parts in their vans for this reason.

In fact I joined RAC partly for this reason as all they charge you for are the parts which I think are about £40 a pop.

I also managed to persuade VW to replace me cost of last lot of these coils... Renault wouldn't on my wifes Scenic!

Good luck.

HTH

Andrew

[goldenoldie]

Spot on bout the coils . caused intermittant misfire. until mine finally went goosed 1 day the other week. was TB /air leak on mine

if the part in question some how starts working again the Codes clear themselves. But only if if ecu "sees" them as working for a pre determined number of starts fro ignition off position

you can see how many times fault has occured ,next to the number of starts with part working needed 2 clear code on vag coms DTC's

if Code will not clear then problem lies with egr .but check however 2 see if it just needs 2 b cleaned before u shell out.