Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: vansboy on 04 March 2008, 19:47:37

Title: Head gasket fixed - now poor MPG
Post by: vansboy on 04 March 2008, 19:47:37
Hi All!

My first time here & already asking for help!!


My 2.5 CDX auto estate 97R, has problems!!

Had the HG done, as we were loosing 1/2lt in 300miles or so. No loss of performance, or water in oil, so not certain if this was REAL cause of coolant loss, as it needed 2 further attempts to fix 'other leaks' after the HG!

But that's hard to quantify, so ignoring that, really. What we do have is MPG prior to repair of 27ish, now lucky to get 21!!

I have been using climate control & max heating/lights during the journey of 30miles, each way, daily, in darkness, so expect some increase in consumption.

But on a run from filling up in Luton, resetting the computer readings & straight onto M1, to start of motorway, daytime, no delays, max 6omph & no heating used, it still only got 23mpg.

So any input welcomed!

Thanks in advance!

VB
Title: Re: Head gasket fixed - now poor MPG
Post by: MutantCav on 04 March 2008, 19:52:10
Motorway travel should be more like 35+ on a 2.5v6...
Title: Re: Head gasket fixed - now poor MPG
Post by: Entwood on 04 March 2008, 19:59:04
Methinks you need a trip to Nottingham to get some live data from a genuine Tech 2 ....  there is something really odd with your description ... garage charges for a head gasket that probably didn't need doing, still has leaks that takes 2 visits, now has poor consumption ???  

My guess is something is either connected wrongly or not connected at all !!!  

Tech2 live data will pin point either ...

Mark DTM is in Nottingham
Title: Re: Head gasket fixed - now poor MPG
Post by: MutantCav on 04 March 2008, 20:13:27
I agree, sounds very wrong...if I was you I would be VERY upset with the garage that they changed the head gasket just because the car was loosing some water when in fact it probably wasnt the cause at all...v6 head gasket hardly ever fails and there are a number of tell tale signs, none of which your car seems to have exhibited...I would certainly be wanting my money back!

My car is a 99 2.5 v6 and is running rough as hell and still managing 23-25mpg...I would agree see if some of the more knowledgable ones on here and there are some very clever people on here (as stated Mark being one of them) can have a look at your car and sort it properly :)
Title: Re: Head gasket fixed - now poor MPG
Post by: VXL V6 on 04 March 2008, 20:22:57
Ignoring all the headgasket / coolant issues (Though always fix the obvious first!) I think there's something else going on such as a Vac leak somewhere.... the plenum has obviously been off while they have been doing the other work so I think it's worth a quick check over.

Title: Re: Head gasket fixed - now poor MPG
Post by: JamesV6CDX on 04 March 2008, 21:50:17
I'm surprised nobody has mentioned this already but,

I suspect they buggered up the cambelt fitting / valve timing. This would have needed to come off to change the HG's obviously, and what are the chances that the garage had a GM setting tool AND know how to use it? ;)

I expect with the crank at TDC the cams are a few degrees out,

hence the combustion is not "in time" and hence not all fuel being injected can be ignited...

Title: Re: Head gasket fixed - now poor MPG
Post by: Marks DTM Calib on 04 March 2008, 21:52:56
What other leaks were fixed after?

Heater bypass valve per chance?

There are a number of things that could be causing it from a vac leak to a dying DIS pack....
Title: Re: Head gasket fixed - now poor MPG
Post by: JamesV6CDX on 04 March 2008, 22:07:49
Quote
What other leaks were fixed after?

Heater bypass valve per chance?

There are a number of things that could be causing it from a vac leak to a dying DIS pack....

Or an incorrectly setup cambelt ;D
Title: Re: Head gasket fixed - now poor MPG
Post by: Marks DTM Calib on 04 March 2008, 22:08:58
Quote
Quote
What other leaks were fixed after?

Heater bypass valve per chance?

There are a number of things that could be causing it from a vac leak to a dying DIS pack....

Or an incorrectly setup cambelt ;D

Yup....but a vac test is MUCH easier to check  :y

When I checked the vac on Paulus's Elite it was low.....found that somebody had connected the auto box breather to the breather bridge and left the main breather dangling!
Title: Re: Head gasket fixed - now poor MPG
Post by: TheBoy on 04 March 2008, 22:11:47
Quote
Quote
Quote
What other leaks were fixed after?

Heater bypass valve per chance?

There are a number of things that could be causing it from a vac leak to a dying DIS pack....

Or an incorrectly setup cambelt ;D

Yup....but a vac test is MUCH easier to check  :y

When I checked the vac on Paulus's Elite it was low.....found that somebody had connected the auto box breather to the breather bridge and left the main breather dangling!
Its comments like that that, despite being the village idiot, I feel intelligent ;D
Title: Re: Head gasket fixed - now poor MPG
Post by: Marks DTM Calib on 04 March 2008, 22:13:10
Quote
Quote
Quote
Quote
What other leaks were fixed after?

Heater bypass valve per chance?

There are a number of things that could be causing it from a vac leak to a dying DIS pack....

Or an incorrectly setup cambelt ;D

Yup....but a vac test is MUCH easier to check  :y

When I checked the vac on Paulus's Elite it was low.....found that somebody had connected the auto box breather to the breather bridge and left the main breather dangling!
Its comments like that that, despite being the village idiot, I feel intelligent ;D

No, your not the village idiot, he drives a tractor......ow :-?
Title: Re: Head gasket fixed - now poor MPG
Post by: vansboy on 04 March 2008, 22:13:55
Much obliged for these helpful & speedy suggestions.

Will talk to the repairers & let you know whats what!

Thanks again!

VB
Title: Re: Head gasket fixed - now poor MPG
Post by: JamesV6CDX on 04 March 2008, 22:14:17
Didn't Fin once have one with a bolt clamped in the autobox breather pipe ;D
Title: Re: Head gasket fixed - now poor MPG
Post by: TheBoy on 04 March 2008, 22:15:29
Quote
No, your not the village idiot, he drives a tractor......ow :-?
But he really wants a Thwaites....
Title: Re: Head gasket fixed - now poor MPG
Post by: Marks DTM Calib on 04 March 2008, 22:17:37
Quote
Much obliged for these helpful & speedy suggestions.

Will talk to the repairers & let you know whats what!

Thanks again!

VB


First thing to do is get them to do a BASIC vac test.....starting on one of the vac hoses and then moving to the plenum brake servo hose.

The most likely cause is they have not put something back correctly after the re-build!
Title: Re: Head gasket fixed - now poor MPG
Post by: shyboy on 05 March 2008, 09:35:12
And don't be afraid to quote OOF opinions to them at the appropriate moment. It will really put them on their toes.