Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Peterbos on 14 November 2011, 14:09:41

Title: Help needed with a 2.5 v6 Engine fault
Post by: Peterbos on 14 November 2011, 14:09:41
Help needed. Location Burnham on Sea Somerset.
I have replaced the aux belt and tensioner on my 2.5 v6.
When I started the engine all was well until it got to temperature. It then cut out. 5 mins later restarted fine only to cut out again and so on.
Checked here and all the simptoms pointed to the crank shaft sensor failing (now replaced).
On completion the engine started ok. As soon as the RPM started to slow down from initial cold start running speed the engine cut and will not restart (left for an hour before trying again).
Does any one live near by who can do a quick diagnosis or have a probable solution to the issue.

Thanks

Pete
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Osprey on 14 November 2011, 14:45:51
Try reading the engine codes using the paperclip test:

http://www.omegaowners.com/forum/index.php?topic=90581.0 (http://www.omegaowners.com/forum/index.php?topic=90581.0)

then post them on here for the experts to interpret.

Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Marks DTM Calib on 14 November 2011, 14:58:30
Was it the tensioner that caused the aux belt to fail?

Is the belt route correctly and driving the water pump?

Is the water pump ok?
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Peterbos on 14 November 2011, 15:44:15
The tensioner pully exploded when the bearing failed and destroyed the aux belt.
The water pump seems fiine no noisey bearings and he belt is operating as it should do.
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Peterbos on 14 November 2011, 15:54:09
Read the paperclip test and watched the vidio.
Just looking for a clip and will post again shortly.
(Not so depressed already)
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: JamesV6CDX on 14 November 2011, 16:13:29
Am only an hr up the M5 in Gloucestershire.... have diag / live data reading / resetting capable kit, along with V6 timing tools and experience with the V6's, not around for a few days but if you get really stuck let me know.

I hope nothing's got caught up in the cambelt  :-\
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: albitz on 14 November 2011, 16:17:55
Sounds to me like the idle control valve needs cleaning. :-\
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Peterbos on 14 November 2011, 16:20:04
Paper clip test done.
3 codes showing
1-2 start of test
7-3 mass air flow sensor voltage low
and the usual 3-1
Which one is the mass air flow sensor.
I did unplug the air intake pipe work to get better access. So are we talking broken wire or dirty plug conections or crackered sensor.
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: JamesV6CDX on 14 November 2011, 16:22:28
An unplugged electrical connection to the MAF wouldn't cause it to stall at ldle.

I'm thinking there's actually nothing up with the MAF, but that, you probably have an airleak somewhere, hecne the symptoms and subsequent code... :y
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Peterbos on 14 November 2011, 16:58:12
I've checked the MAF sensor plug for a bad conection and all seems well.
Also checked all the vacuum pipes and conectors at the front of the engine incase I'd dislodged one but can find nothing to report.
The engine will not fire at all now following the initial start and stop after less then a minuets running.
Title: Re: Help needed with a 2.5 v6 Engine fault
Post by: Andy H on 14 November 2011, 19:04:24
Just a random thought.

After 1 minute of cold running could the engine be flooded with petrol? (or does the ECU have protection built in to prevent flooding?)