Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: marcbucks on 12 July 2010, 10:29:16

Title: Won't Start when hot!
Post by: marcbucks on 12 July 2010, 10:29:16
Hi,

I have an Omega 2.5 V6 auto 99 plate.

Please any advice. My Omega yesterday would not start, and ended up calling the breakdown for a tow home.

The car normally runs smooth purrs like a kitten even with very high mileage, but rescently the car would not start straight awaywhen it had  been run for a short period. It would turn over but not even try to catch. Leave it for 10 mins and started without a thought!

Yesterday it was very hot outside but went to the car in the afternoon and took 20 mins to start drove it 10 miles had a cuppa went back to the car and the car would not start for love nor money. I got it to attempt to start it and chugged spluttered but quickly died.
Even leaving it to cool for over an hour, it would not even try to start.

Tested the spark and it was excellent as is the battery.

The road side mechanic basically sprayed plus starter spray down the air filter which started the car in seconds, left it to run for 10 minutes but pulled off and stalled and it died and that was it! Tow home.

With the mechanic saying it could be the cold start injector or the fuel pump i was pretty set for a very expensive garage bill.

I went out to the car this morning and bang starts on first contact!

Reading Omega Owners forums it was saying coolant sensor, crankshaft sensor etc.

The only odd thing with the car is the external temperature sensor always reads about 6 to 8 oC lower than the actual real temperature outside for example yesterday it got to about 28oC outside yesterday and the dash read 19oC. I have replaced the sensor, but the problem did not go. I paid it no attention but I have added this bit of info if it helps.

Please any advice on running a diagnostic or where to look for the fault would be great.

Unfortunatly my tech knowledge with vehicles stop with old cars and buses and the days of Magnetos and starting by hand with the engine set to retarded. but quite happy to get dirty.
Title: Re: Won't Start when hot!
Post by: Entwood on 12 July 2010, 10:35:15
First things first .. paperclip test :

http://www.omegaowners.com/forum/YaBB.pl?num=1189022687

Then post up the results ...

I would not be surprised if you have a code 19 - Cranksensor .... description of the fault leads to that .. pretty easy fix..

http://www.omegaowners.com/forum/YaBB.pl?num=1174321688

just a matter of making sure you get the right one !!
Title: Re: Won't Start when hot!
Post by: TheBoy on 12 July 2010, 12:25:04
Might be worth filling in your location, maybe nearby members are willing to point you in right direction ;)


But, as stated, do a paperclip test and see what that says :y
Title: Re: Won't Start when hot!
Post by: marcbucks on 12 July 2010, 12:42:46
Thank you for replies,

O.K.

Have gone to car and done the paper clip test.

I am getting no error, it just repeats the 12 (start/end) of test.

I did this both with the engine cold and after running it for 30 mins but not taken it off the drive for fear of stalling.

I hope this info help.

Many Thanks

Marc.

Thanks TheBoy will update location/profile and for info; I'm in Milton Keynes.
Title: Re: Won't Start when hot!
Post by: tunnie on 12 July 2010, 13:22:50
test is supposed to be done without engine running...
Title: Re: Won't Start when hot!
Post by: TheBoy on 12 July 2010, 13:52:17
Dare drive it to deepest Brackley.  Assuming you know your way off the grid ;D ;D ;D
Title: Re: Won't Start when hot!
Post by: TheBoy on 12 July 2010, 13:53:04
Quote
test is supposed to be done without engine running...
v6, it matters not ;).  In fact with engine off, this engines gives a 31
Title: Re: Won't Start when hot!
Post by: marcbucks on 12 July 2010, 13:53:10
Sorry the reason I did it with engine running as got the message 31.
Yes ran the paper clip test with engine off, with both a cold and hot enigne.
I got the code 12 followed by code 31 (i believe on the V6 is to say engine not running). Followed again by code 12 etc
I hope this helps,
Marc
Title: Re: Won't Start when hot!
Post by: marcbucks on 12 July 2010, 13:57:51
I haven't been near Brackley Northants in a while but just other side of Buckingham. Not enough roundabouts! lol
Title: Re: Won't Start when hot!
Post by: TheBoy on 12 July 2010, 14:24:49
The offer is there if you want someone to take a look.  Can't say we will definately find the fault, but will allow us to eliminate some things.


If you prefer local garages, I'd personally avoid Evans Halshaw at Crownhill, useless incompitent robbing bastards, but Jim Grayson has a good name :y
Title: Re: Won't Start when hot!
Post by: Andy B on 12 July 2010, 14:29:31
Quote
...
Have gone to car and done the paper clip test.

I am getting no error, it just repeats the 12 (start/end) of test. ......

A failed or failing crank sensor doesn't always throw up a fault code 19 ....... or so I'm lead to believe.


and your car doesn't have a cold start injector  :y in the early days of injection, some systems used an extra injector as an aid to starting ie a kind of choke  ;)
Title: Re: Won't Start when hot!
Post by: russ b on 12 July 2010, 19:43:55
I use to have a vectra with exactly same problem turned out after much expense it was a 8 pound thetmostat sensor I would visit the boy to eliminate silly things like this before you spend out on her
Title: Re: Won't Start when hot!
Post by: harpersimon on 12 July 2010, 20:22:21
CPS  - no doubt - if it runs cold, then doesnt start.
Title: Re: Won't Start when hot!
Post by: Andy H on 12 July 2010, 20:43:52
When the crank sensor failed on my 1994 2.5 V6 it didn't bring up a 19 code.

What I did notice was that on the occasions when the crank sensor wasn't giving a signal the engine management light stayed lit but when it was working the light went out instantly.
Title: Re: Won't Start when hot!
Post by: marcbucks on 13 July 2010, 12:24:50
Update :

Took the car for a small drive of a mile and again got hot quickly and stalled. Left it for 45 mins and started drove up the hill towards my house and then completely cut out again. I tried the paperclip test on pins 4 and 6 and all i got was code "12" and "31" or when i had tried to turn the engine over just a code "12" but not running.

Had the breakdown people to take car home as couldn't even get it to fire! Even cold (although i have not gone to try this morning!)

He said it was possibly the engine coils as they looked a little rough after the rescent weather or the crankshaft sensor.

Unfortunatly it looks like a trip to a garage as i doubt the car will get very far on its own steam! :'(
Title: Re: Won't Start when hot!
Post by: TheBoy on 13 July 2010, 18:47:28
Where in MK?
Title: Re: Won't Start when hot!
Post by: harpersimon on 15 July 2010, 23:25:42
Get someone to give you a lift to local VX, buy a crank sensor and throw it in. 99% its that, and if not its not an expensive part :-) (there arent any in Brackley though :-) )