Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: B52 on 19 September 2020, 14:45:00

Title: 2.6 V6 cut out, now won't start
Post by: B52 on 19 September 2020, 14:45:00
2002 MV6 auto hasn't seen much use since March, for obvious reasons.

Replaced the battery a month ago and all well. Not used since then. Today, started up and drove normally round the block leaving it to idle while getting ready for a wash. Ran for about 10 minutes and then cut out, ignition and oil lights on.

Cranks strongly, recognises gear selector, battery connections ok, belt intact - won't fire. So I'm thinking:

- old/bad fuel (quarter full)
- fuel pump
- crank sensor
- MAF sensor

Or am I missing something obvious, hopefully simpler? Thanks...
Title: Re: 2.6 V6 cut out, now won't start
Post by: biggriffin on 19 September 2020, 14:48:36
Sounds like crank sensor,,,
Title: Re: 2.6 V6 cut out, now won't start
Post by: Nick W on 19 September 2020, 15:00:46
Bad fuel is possible, add a couple of gallons


Fuel pump should turn when the engine does BUT
that relies on a signal the crank sensor


failed MAF tends to run, but not idle.




Crank sensor is by far the most likely. Genuine Vx unless like you like risky gambling
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 19 September 2020, 15:04:33
Ok... not put any fuel in this year, so probably try some fresh first.

If I'm reading previous posts right, it's crank sensor 90540743 and ideally from Vauxhall (not unbranded ebay nonsense)
Title: Re: 2.6 V6 cut out, now won't start
Post by: Nick W on 19 September 2020, 15:17:07
Ok... not put any fuel in this year, so probably try some fresh first.

If I'm reading previous posts right, it's crank sensor 90540743 and ideally from Vauxhall (not unbranded ebay nonsense)


You can check what's in the fuel rail by using the pressure test port(which is a standard schraeder valve)
Title: Re: 2.6 V6 cut out, now won't start
Post by: New POD on 19 September 2020, 15:35:07
Mine was the crank sensor. 

To check the fuel pump was working, I simply cracked the pipe connection slightly where it joint the engine, and fuel came out whilst cranking.
No smell of in burnt fuel out the exhaust?

The ECU needs to know where the crank is so it knows when to spark and when to let fuel in.

I know the experts demand to fit a GM boxed crank sensor, but I have put a spare Bosch one in the boot at less than half the price.  If it goes, the RAC can fit it at the side of the road. Or take me home.
Title: Re: 2.6 V6 cut out, now won't start
Post by: Nick W on 19 September 2020, 15:41:39
The genuine only(and it applies to the crank sensor on any engine) recommendation is for long-term durability and frustration reduction. They're not that much more expensive than a branded one.
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 19 September 2020, 15:47:50
Replies appreciated  :)

Pretty sure fuel is likely 9-12 months old so easy to try some fresh over the weekend. Car only has 51k miles but crank sensor has never been replaced so guess I've been lucky so far.
Title: Re: 2.6 V6 cut out, now won't start
Post by: jb on 20 September 2020, 06:30:06
odds on its the crank sensor
Title: Re: 2.6 V6 cut out, now won't start
Post by: johnnydog on 20 September 2020, 11:44:41
Quote
If I'm reading previous posts right, it's crank sensor 90540743 and ideally from Vauxhall (not unbranded ebay nonsense)

Yes, that is the correct VX part no for the crank sensor.
Title: Re: 2.6 V6 cut out, now won't start
Post by: biggriffin on 20 September 2020, 12:22:06
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.amazon.co.uk/Genuine-Vauxhall-Crankshaft-Position-90540743/dp/B019OTZ750&ved=2ahUKEwivkISUzvfrAhWHiFwKHT1EDhoQFjAMegQIBRAB&usg=AOvVaw3RL0NrwUOr98Ofg1KWhjJQ

 Bought my last one here, comes from GM dealer.
Title: Re: 2.6 V6 cut out, now won't start
Post by: Doctor Gollum on 20 September 2020, 14:10:31
Fuel pump, fuel condition and fuel level being critical factors in this case.  ;)
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 20 September 2020, 14:55:53
Update from today

5 litres of new fuel in - heard pump priming, started immediately, idled and revved normally. Then stopped abruptly (no misfire or any other sound) after about 10 minutes and won't restart. Only oil and ignition lights on - oil light goes off when cranked.

Temp gauge had just started to move, but not to where the thermostat would open. Can't think of anything else that might happen around the 10 minute mark. I suppose bad/dirty fuel is still possible but the same time from start to stop makes me think it's electronic.

Crank sensor seems to be a reasonable place to start.
Title: Re: 2.6 V6 cut out, now won't start
Post by: Doctor Gollum on 20 September 2020, 15:18:53
What other work has been done in the engine bay?
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 20 September 2020, 15:24:35
What other work has been done in the engine bay?

Battery replaced in July - started and drove normally for several hours. Nothing else recently.
Title: Re: 2.6 V6 cut out, now won't start
Post by: Doctor Gollum on 20 September 2020, 15:25:08
Swap out the fuel filter, add another two gallons and report back ;)
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 20 September 2020, 23:20:06
A little progress... after 6 hours, moved it to a spot from where it can be towed if need be. Same as before - started and ran for 10 minutes and cut out.

Walked to get another 5 litres of fuel, which took about an hour. It's now just under half full. This time, it started and ran/revved as normal for 30 minutes without cutting out. Switched it off and removed key. Started again and ran/revved as normal for another 20 minutes. Cooling fans cycled as normal, no lights on dash.

So I plan to leave it overnight and try another 30 minute idle/restart tomorrow. If that goes ok, I'm hoping it should be safe to drive about 1km from here to fill up with fuel.

New fuel filter should arrive this week and I'll get a crank sensor to have ready just in case.
Title: Re: 2.6 V6 cut out, now won't start
Post by: Doctor Gollum on 21 September 2020, 00:17:05
Modern petrol lasts a bit longer than lettuce kept in a fridge.

That said, the Omega is pretty susceptible to fuel starvation t anything much below a quarter tank, especially if on a slope to the left or front. The estates suffer worse, but it does affect the saloons as well.

From experience, it can take 4 gallons extra to restart once it cuts out.

Should be OK, just keep it topped up with fresh fuel  :y
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 21 September 2020, 00:27:49
It's been parked up on a slope to the left for the last six months or so yeah...

I've had KW02 since 2003 and this is the first time it's acted up like this. Guess it's time for some attention and TLC.
Title: Re: 2.6 V6 cut out, now won't start
Post by: Doctor Gollum on 21 September 2020, 00:31:12
That'll be the problem then ;)

Use it for a bit and then create a job list :y
Title: Re: 2.6 V6 cut out, now won't start
Post by: B52 on 23 October 2020, 14:36:09
Solved - crank sensor, so answers appreciated

Other good news - MoT passed (two advisories) and now doing a full service

Will likely run it for the time being but after 17 years, am toying with the idea of moving it on. Will post it on here first.

Title: Re: 2.6 V6 cut out, now won't start
Post by: ronnyd on 23 October 2020, 15:16:46
Solved - crank sensor, so answers appreciated

Other good news - MoT passed (two advisories) and now doing a full service

Will likely run it for the time being but after 17 years, am toying with the idea of moving it on. Will post it on here first.


You'll need over 250 posts to sell on here. ;) So get typing.