Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Neil_MV6 on 01 December 2010, 09:04:30

Title: Miss-fire under load
Post by: Neil_MV6 on 01 December 2010, 09:04:30
Last night I went out in the car for the first time this week, so the car's been sat for a few days in the cold. Because it was icy I used the ice/snow button on the auto box to get up the hill, but noticed it was miss-firing.

This has happened on a couple of occasions before when starting from cold but it's been successfully rectified by switching the engine off and restarting each time. This time however, the problem seems to be a bit more persistent.

On the way to work this morning it was miss-firing so I pulled over, switched off and restarted, which did the trick for a while until I came to some lights and had to stop.

While idling in 'drive', it started miss-firing again and now seems to do it whenever there's some moderate load on the engine.

Tick-over and revving while in Neutral is fine (unless I really boot it hard...then it miss-fires again).

So basically it's miss-firing under load. What should I check first? I know plugs are an obvious but is there anything else I should look at while I'm there?

2002 3.2 MV6 Auto.

Cheers guys
Neil   :y
Title: Re: Miss-fire under load
Post by: The Red Baron on 01 December 2010, 09:12:39
cam covers could be leaking oil into the plug wells, this will bugger the dis packs eventualy.
Title: Re: Miss-fire under load
Post by: henryd on 01 December 2010, 11:52:44
as red baron says oil or maybe water beneath coil packs,best to whip them out and check and perhaps change spark plugs while you are there if you don't know how long they have been fitted,pedal trick should give you codes to narrow down which side of engine is causing issues
Title: Re: Miss-fire under load
Post by: Marks DTM Calib on 01 December 2010, 12:00:44
Deffo a HT breakdown of some sort, you may find water around your 2-4-6 coil packs.
Title: Re: Miss-fire under load
Post by: Neil_MV6 on 01 December 2010, 15:07:03
Cheers for the advice chaps.

I'm starting to think that maybe this has been caused by me pouring loads of warm water over the windscreen in the mornings to defrost it?? I've been using a couple of 2-litre milk containers each time.  ::)

Is it likely that this has caused permanent damage or will it be ok if I can dry it all out?
Title: Re: Miss-fire under load
Post by: Kneepad on 01 December 2010, 15:12:59

You may be lucky and find that once it's dried out it will be OK.   :y
You may not be so lucky with the windscreen, when it cracks you will have to replace it.   :(
Title: Re: Miss-fire under load
Post by: MutantCav on 01 December 2010, 15:54:03
Probably water in the plug wells...probably worth drying them out with a hairdryer as a start point...also you should only use cold water on your windscreen (or better still cover the screen over night to stop the ice) as the sudden change i temperature can crack the screen
Title: Re: Miss-fire under load
Post by: Neil_MV6 on 04 December 2010, 11:51:16
Update:
Bought new spark plugs... I did the drivers side first and discovered that two of the plug wells were full of oil. I thought this must be the cause but after cleaning it all up and popping new plugs in the miss-fire remained. One of the coil packs looked quite cracked so I thought "pants, must be that".

Anyway, moved onto the passenger side which looked ridiculously awkward at first, but I followed Markjay's guide http://www.omegaowners.com/forum/YaBB.pl?num=1169337137/0 and it wasn't too difficult.

It was the last plug, right at the back on the passengers side which was covered in wet gunk. Replaced and miss-fire cured.

No more pouring water on the windscreen.  :y
Title: Re: Miss-fire under load
Post by: RobG on 04 December 2010, 11:56:37
Quote
Update:
Bought new spark plugs... I did the drivers side first and discovered that two of the plug wells were full of oil. I thought this must be the cause but after cleaning it all up and popping new plugs in the miss-fire remained. One of the coil packs looked quite cracked so I thought "pants, must be that".

Anyway, moved onto the passenger side which looked ridiculously awkward at first, but I followed Markjay's guide http://www.omegaowners.com/forum/YaBB.pl?num=1169337137/0 and it wasn't too difficult.

It was the last plug, right at the back on the passengers side which was covered in wet gunk. Replaced and miss-fire cured.

No more pouring water on the windscreen.  :y
When are you gonna do the camcover gasket then :-?
Title: Re: Miss-fire under load
Post by: Neil_MV6 on 04 December 2010, 16:20:38
When it's not so bloomin cold..... ;D