Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: eco16v on 08 July 2025, 13:04:05

Title: Recommissioning a barn find mv6
Post by: eco16v on 08 July 2025, 13:04:05
Hi guys, been about 15 years since I last owned an omega, but I have very recently acquired a pre facelift 99 3.0 mv6 manual with 54k miles that has been dry stored in a barn from 2011. She is currently a non runner but engine is turning over freely by hand and also in the key, I have spark but no fuel, I’m guessing fuel pump and fuel filter are my main issues but is there anything else I should be looking at? Cheers
Title: Re: Recommissioning a barn find mv6
Post by: TheBoy on 08 July 2025, 13:08:14
Like all GM's of the era, fuel pump relay.  I just check it's not immobilised (flashing EML).

If not immobilised, start by checking power to fuel pump, and they work back electrically, or forward on fuel system from there.
Title: Re: Recommissioning a barn find mv6
Post by: eco16v on 08 July 2025, 13:11:50
Thankfully the eml is not flashing and there is power going to the fuel pump but no fuel getting to the engine. I’ve bought a new pump and filter so will start with those. 
Title: Re: Recommissioning a barn find mv6
Post by: TheBoy on 08 July 2025, 13:16:37
Whilst in there, might be worth cleaning the tank out, if its sat for a decade and a half.
Title: Re: Recommissioning a barn find mv6
Post by: Nick W on 08 July 2025, 13:40:48
Whilst in there, might be worth cleaning the tank out, if its sat for a decade and a half.


Before you fit the new pump, disconnect the fuel rail and blow out both the supply and return lines under the car. You don't want any old fuel getting near the engine.
Title: Re: Recommissioning a barn find mv6
Post by: eco16v on 08 July 2025, 16:05:09
Cheers guys will definitely blow the lines out while I have them off at the back to do the pump and filter.
Title: Re: Recommissioning a barn find mv6
Post by: Andy H on 09 July 2025, 02:32:21
Did someone say cranksensor?

OK - just my imagination

Trying to remember whether the ECU needs to see a cranksensor signal before it runs the pump.

You should see the rev counter needle move off the stop when cranking.
Title: Re: Recommissioning a barn find mv6
Post by: Doctor Gollum on 09 July 2025, 10:06:38
Did someone say cranksensor?

OK - just my imagination

Trying to remember whether the ECU needs to see a cranksensor signal before it runs the pump.

You should see the rev counter needle move off the stop when cranking.
It does. Ignore to post 2 runs the pump for a split second. Then it remains off until the crank and cam sensors confirm correct rotation ;)

There are two purple relays in the engine bay fuse box. One is the pump and one is the injector power. They can be swapped over for testing purposes, although in this case, replacing the pump is a reasonable first step.
Title: Re: Recommissioning a barn find mv6
Post by: Doctor Gollum on 09 July 2025, 13:37:58
Ignition to pos2


Opposing robots :-X
Title: Re: Recommissioning a barn find mv6
Post by: Ricky043 on 10 July 2025, 09:26:14
When I did the fuel pump last September I had trouble finding the pre shaped rubber fuel line that connected the top of the fuel pump to the underside of the fuel pump cover.
Couldn't find a vauxhall one for the omega (mine is a 1999 v6 2.5) then came across one for a Vectra with the same engine that was a perfect replacement for mine which had gone gooey and was starting to disintegrate.

From my Ebay listing there are several part numbers showing as follows:
Opel 820415
9157561
RAPRO: R18258
and MFL1107 ( I think this is the Gates part number, which mine was)
I got mine from Carpartsinmotion on ebay but I'm sure it must be available elsewhere.
Title: Re: Recommissioning a barn find mv6
Post by: eco16v on 10 July 2025, 18:27:32
Little update, replaced the fuel filter and in tank pump, blew out the lines and gave the tank a clean and she fired up after a few seconds. Seems to be ticking over quite nicely for a car that hasn’t been started in 14 years. Thanks for the advice guys.
Title: Re: Recommissioning a barn find mv6
Post by: Migv6 le Frog Fan on 10 July 2025, 22:08:23
Good to hear.  :y
Title: Re: Recommissioning a barn find mv6
Post by: TheBoy on 11 July 2025, 08:01:33
Another 3l roars into life :y

I believe the 3.0l is the best of all petrol engines fitted to the Omega-B.  The 3.2 is compromised by penny pinching, resulting in approximately similar performance but with woeful economy (as is the 2.6 compared to the 2.5), and all others are a little underpowered, yet don't give a significant increase in economy.  The 3l is surprisingly economical given its age, assuming you don't hoof it everywhere.
Title: Re: Recommissioning a barn find mv6
Post by: eco16v on 11 July 2025, 18:33:44
I previously had a 2.5 facelift and it was a comfy old bus, fuel economy was woeful tho lol, I was originally going to sell this 1 but now that I’ve got it running and see that all the electrics work as they should I think I will keep it and get it back on the road. I’ve done a bit of digging into its history and it’s an ex undercover police car and seems to be quite scarce in red.
Title: Re: Recommissioning a barn find mv6
Post by: Doctor Gollum on 11 July 2025, 20:48:58
If it's bright red, it was probably a Met Police car.

Now it's running, next order of business should be a cambelt change ;)
Title: Re: Recommissioning a barn find mv6
Post by: eco16v on 11 July 2025, 22:10:17
She’s Tizian red, ex NI police car. Full service and cambelt change is next on the list for it :y