Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: eliteomegaman on 04 May 2010, 09:19:50

Title: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 09:19:50
Morning all  :)
Have posted a few times about my facelift 2.5 elite with a misfire.
Just to re-cap -:
NOTHING showing on paper clip test or Tech 2
Coil pack replaced
Cam shaft sensor replaced (mechanic said fault code shown on tech 2 BUT didn't realise that the engine had to be running for it to clear!)
New spark plugs replaced
New HT Leads replaced (correctly fitted onto coil pack & no leads loose)
New fuel filter fitted
Compression test done y/day but nothing found!
Have now been advised that it could well be that the Exhaust Manifold Gasket could be the problem OR injectors (although 2 lots of cleaner where put in a couple of months ago when the problem first happened).
The exhaust does sound as if its blowing & i just wanted to ask anyone out there if they think that this could well be the cause of the bad misfire & if so is it an expensive job to do (i know the gaskets are only a few quid on ebay) labour wise?
I'm at the end of my tether with this & it's cost me a small fortune up to know which has completely made me skint!! :'(
PLEASE HELP!!!! :( :( :(
Title: Re: Exhaust Manifold Gasket
Post by: Elite Pete on 04 May 2010, 09:22:42
Quote
Morning all  :)
Have posted a few times about my facelift 2.5 elite with a misfire.
Just to re-cap -:
NOTHING showing on paper clip test or Tech 2
Coil pack replaced
Cam shaft sensor replaced (mechanic said fault code shown on tech 2 BUT didn't realise that the engine had to be running for it to clear!)
New spark plugs replaced
New HT Leads replaced (correctly fitted onto coil pack & no leads loose)
New fuel filter fitted
Compression test done y/day but nothing found!
Have now been advised that it could well be that the Exhaust Manifold Gasket could be the problem OR injectors (although 2 lots of cleaner where put in a couple of months ago when the problem first happened).
The exhaust does sound as if its blowing & i just wanted to ask anyone out there if they think that this could well be the cause of the bad misfire & if so is it an expensive job to do (i know the gaskets are only a few quid on ebay) labour wise?
I'm at the end of my tether with this & it's cost me a small fortune up to know which has completely made me skint!! :'(
PLEASE HELP!!!! :( :( :(
Don't get the cheap Ebay ones, only use the multi layer genuine Vauxhall ones from a dealer ;)
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 09:47:07
Cheers for the message Pete & the quote
All i can say is J-E-S-U-S didn't realise it was so expensive  :'( :'( :'(!!!!
Could the misfire be caused by the Exhaust Manifold Gasket leaking???
Title: Re: Exhaust Manifold Gasket
Post by: V6Astra F on 04 May 2010, 09:55:39
Also had quite a random missfire when starting the car when it was still hot , turned out to be the MAF sensor as soon as I unplugged it the car ran fine
Title: Re: Exhaust Manifold Gasket
Post by: Marks DTM Calib on 04 May 2010, 10:00:00
Quote
Cheers for the message Pete & the quote
All i can say is J-E-S-U-S didn't realise it was so expensive  :'( :'( :'(!!!!
Could the misfire be caused by the Exhaust Manifold Gasket leaking???

I would say no and given what your mechanics has changed....its time for a new mechanic!
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 10:27:38
Quote
Quote
Cheers for the message Pete & the quote
All i can say is J-E-S-U-S didn't realise it was so expensive  :'( :'( :'(!!!!
Could the misfire be caused by the Exhaust Manifold Gasket leaking???

I would say no and given what your mechanics has changed....its time for a new mechanic!
[/highlight]
Trouble is i have a car that's misfiring & 3 different people don't know what the problem is & can only guess what it might be - plugs? renewed, ht leads? renewed, compression test? done, fuel filter? done, loose lead on coil pack? nope, paper clip test? done with nothing showing & the list goes on!!!
If it is the Exhaust Manifold Gasket then at an estimated £170 i'm f**ked cos not got a pot to p**s in!!!!
Maybe some-one on this site has had the same problem & could give me advise as i'm not mechanically minded  :-[
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 10:30:18
Quote
Also had quite a random missfire when starting the car when it was still hot , turned out to be the MAF sensor as soon as I unplugged it the car ran fine
My misfire is there all the time as soon as i accelerate  :'(
Title: Re: Exhaust Manifold Gasket
Post by: Marks DTM Calib on 04 May 2010, 10:31:11
You say the cam sensor was replaced (strange), do you mean the crank sensor?
Title: Re: Exhaust Manifold Gasket
Post by: V6Astra F on 04 May 2010, 11:08:10
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Quote
Also had quite a random missfire when starting the car when it was still hot , turned out to be the MAF sensor as soon as I unplugged it the car ran fine
My misfire is there all the time as soon as i accelerate  :'(

Mine had the missfire/stuttering from 1800-2700 rpm also with no eml light or codes stored . Just unplug it and go for a test drive .
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 11:10:16
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You say the cam sensor was replaced (strange), do you mean the crank sensor?
Sorry ur dead right i mean the crank sensor code 31  :-[
Title: Re: Exhaust Manifold Gasket
Post by: tunnie on 04 May 2010, 11:11:01
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You say the cam sensor was replaced (strange), do you mean the crank sensor?
Sorry you are dead right i mean the crank sensor code 31  :-[

Code 31 is normal when the engine is not running, code 19 indicates crank sensor failure.

Hope you did not replace it based on 31 code!
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 11:12:39
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Quote
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Also had quite a random missfire when starting the car when it was still hot , turned out to be the MAF sensor as soon as I unplugged it the car ran fine
My misfire is there all the time as soon as i accelerate  :'(

Mine had the missfire/stuttering from 1800-2700 rpm also with no eml light or codes stored . Just unplug it and go for a test drive .
[/highlight]
How do i do that?
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 11:16:19
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You say the cam sensor was replaced (strange), do you mean the crank sensor?
Sorry you are dead right i mean the crank sensor code 31  :-[

Code 31 is normal when the engine is not running, code 19 indicates crank sensor failure.

Hope you did not replace it based on 31 code!
[/highlight]
YES!!!! My mechanic replaced it  :-? not knowing that on the tech 2 test code 31 shows untill the engine is fired up - when i told him he didn't charge me for his embarrasment  ;D
Title: Re: Exhaust Manifold Gasket
Post by: tunnie on 04 May 2010, 11:17:11
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Quote
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Also had quite a random missfire when starting the car when it was still hot , turned out to be the MAF sensor as soon as I unplugged it the car ran fine
My misfire is there all the time as soon as i accelerate  :'(

Mine had the missfire/stuttering from 1800-2700 rpm also with no eml light or codes stored . Just unplug it and go for a test drive .
[/highlight]
How do i do that?

Unplug MAF sensor :)
Title: Re: Exhaust Manifold Gasket
Post by: tunnie on 04 May 2010, 11:17:30
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Quote
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You say the cam sensor was replaced (strange), do you mean the crank sensor?
Sorry you are dead right i mean the crank sensor code 31  :-[

Code 31 is normal when the engine is not running, code 19 indicates crank sensor failure.

Hope you did not replace it based on 31 code!
[/highlight]
YES!!!! My mechanic replaced it  :-? not knowing that on the tech 2 test code 31 shows untill the engine is fired up - when i told him he didn't charge me for his embarrasment  ;D

I would change your mechanic  :y
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 11:24:34
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Quote
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You say the cam sensor was replaced (strange), do you mean the crank sensor?
Sorry you are dead right i mean the crank sensor code 31  :-[

Code 31 is normal when the engine is not running, code 19 indicates crank sensor failure.

Hope you did not replace it based on 31 code!
[/highlight]
YES!!!! My mechanic replaced it  :-? not knowing that on the tech 2 test code 31 shows untill the engine is fired up - when i told him he didn't charge me for his embarrasment  ;D

I would change your mechanic  :y
;D ;D ;D Hahaha have had ''3'' different people look at this car - thinking of putting it on YOU-TUBE  :D :D :D!!!!
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 11:31:49
How do i unplug Maf sensor & where do i find it?
Looked on Maintenance Guide Index but can't find an entry  :-?
Title: Re: Exhaust Manifold Gasket
Post by: Elite Pete on 04 May 2010, 11:37:50
Do you know if the crank sensor he fitted was a genuine one or not?
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 11:45:24
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Do you know if the crank sensor he fitted was a genuine one or not?[/quote]
Said he got a new one which would have been genuine BUT knowing him he might have got one from the scrap yard!
Having said that if this crank sensor is no good wouldn't it show up on a tech 2 test?
Title: Re: Exhaust Manifold Gasket
Post by: V6Astra F on 04 May 2010, 14:05:25
Heres a pic I marked the location of the MAF sensor .
(http://i127.photobucket.com/albums/p131/Angeleyed200is/15042010307-2.jpg)

Note that this is on a Vectra B intake but it should give you an idea of what to look for  :y
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 14:24:27
Quote
Heres a pic I marked the location of the MAF sensor .
(http://i127.photobucket.com/albums/p131/Angeleyed200is/15042010307-2.jpg)

Note that this is on a Vectra B intake but it should give you an idea of what to look for  :y
Thanks for that but its different on the Omega  :(

Title: Re: Exhaust Manifold Gasket - missfiring/stuttering!!!
Post by: eliteomegaman on 04 May 2010, 14:29:39
Have read somewhere on this site that the MAF sensor is 2nd down on the big pipe coming from the air box (hope that's correct?)
Unplugged it & couldn't start the engine! Must be doing something wrong!!  :( :(
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 04 May 2010, 21:36:25
When i took my car to Captain Zok at easter with my problem his son did a dignostic check & couldn't find any faults.
He did find that spark plug no.6 was cracked & getting an oil bath!
The Capatain said that the cats where knackered but 1st port of call would be to change the plugs & HT leads which as previously mentioned have now been done (y/day one of the brand new plugs - one week old, was a different colour & replaced but didn't help the problem!
Could the knackered cats be the cause of the misfiring/stuttering  :-? :-? :-?
Title: Re: Exhaust Manifold Gasket
Post by: Darth Loo-knee on 04 May 2010, 22:05:50
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When i took my car to Captain Zok at easter with my problem his son did a dignostic check & couldn't find any faults.
He did find that spark plug no.6 was cracked & getting an oil bath!
The Capatain said that the cats where knackered but 1st port of call would be to change the plugs & HT leads which as previously mentioned have now been done (y/day one of the brand new plugs - one week old, was a different colour & replaced but didn't help the problem!
Could the knackered cats be the cause of the misfiring/stuttering  :-? :-? :-?

Hold on a minute mate.
A missfire without a code would point I would say to a HT problem. Spark Plugs, Leads & Dispack.
Now you say your plugs that have been in for a week.. that one is a different colour.. where is it a different colour on the electrodes? or on the white part that the leads go onto?
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 05 May 2010, 00:19:42
Hia Darth
i'll have to ask my neighbour as it was him that has done the recent work & told me the new plug was a different colour but didn't tell me where on the plug. have to get back to u on that.
what could be the problem when a plug turns a different colour?
Title: Re: Exhaust Manifold Gasket
Post by: JasonH on 05 May 2010, 12:58:49
If you have a cam cover gasket leak and the oil is leaking into the spark plug wells that is likely to be the cause of the misfire. Engine oil is full of tiny metal particles which can short the plug out.
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 05 May 2010, 18:22:14
When Captain Zok's son had a look No. 6 plug was cracked & swimming in oil   :o
Monday when further tests were done & ht leads replaced one of the new plugs was a different colour (not sure which plug) & the car has only travelled a mile or so - if its the rocker cover then could this be the cause of the misfire/stuttering   :-?
So far i've had 3 people with 3 different theories -
1. Exhaust manifold gasket
2. Knackered cats
3. Leaking rocker covers
I'll take a poke in the dark & based on the different coloured plug i'd say no. 3   
Anyone want to participate in this exciting guessing game  :-? :( :-/ 
Title: Re: Exhaust Manifold Gasket
Post by: Marks DTM Calib on 05 May 2010, 18:27:59
Right....lets consider idle:

1) Exhaust manifold would need to be falling off to cause an idle missfire.......particularly when first started and running open loop.

2) Cats are a possible.....but you say its running rough so that sounds unlikely (but not impossible).

3) Leaking cam cover gaskets.....possible as this could cause a miss fire.
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 05 May 2010, 18:45:08
Thank you Mr Administator  :y
This problem has been going on for so long now that i'm sure its got a mention in the Doomsday Book  ::)
I know that my wallet has never been so cold due to it being empty & to be totally honest i'm sure rocker cover gaskets replacement will be well over £100 & funds won't stretch that far  :'(
But at least i can sleep at night now knowing what the problem probably is  :y
Title: Re: Exhaust Manifold Gasket
Post by: Marks DTM Calib on 05 May 2010, 18:58:01
Well....as a starter for ten, clean all the breather system out and then clean the plug wells out.

This will cost about 3 quid and may sort it short term
Title: Re: Exhaust Manifold Gasket
Post by: eliteomegaman on 05 May 2010, 19:03:05
Will do & thanks again  :y
If this works i'll leave u a little something in my will  ;)
Title: Re: Exhaust Manifold Gasket
Post by: tidla on 05 May 2010, 19:12:27
in the old days carbs and stuff a misfire could be caused due to a weak mixture.
i know with closed loop system its supposed to self regulating..
if excess air is getting in from other than measured sources..
the lambda sensor is registering a rich mix and turning things down..
might by worth checking the exhaust readings.. :-?
Title: Re: Exhaust Manifold Gasket
Post by: tidla on 05 May 2010, 19:29:26
Quote
in the old days carbs and stuff a misfire could be caused due to a weak mixture.
i know with closed loop system its supposed to self regulating..
if excess air is getting in from other than measured sources..
the lambda sensor is registering a rich mix and turning things down..
might by worth checking the exhaust readings.. :-?

just re read your topic..

1. is the cam covers still leaking?
2.the plenum chamber and associated pipework needs to be checked for splits disconections/ air leaks.
3. no codes.. concentrate on mechanical items.
4 checking/inspecting is cheap. :)

5 .egr valve sticking allowing dirty air in.
6.idle valve sticking slightly open.