Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: peteelite on 18 October 2011, 20:45:37
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Hello everyone
My last real posts were around August LAST year when my cam belt went and I posted questions about wether my car was worth fixing, well long story short I still have my Elite after replacing all 24 valves (amongst many other parts ) and the motor runs fine...but,and there is always a but, a very random fault that was there before the engine re build has re emerged. Let me explain...
Sometimes (and I must stress,very rarely) the car will not start up when hot. Example 1: after one hour on the motorway,stop for fuel (10 mins) try to re start and engine will crank well but not start. Leave it for five mins and it will start straight away.
Example 2: short trip to supermarket (engine not hot but up to temp) shop for an hour or so..same thing , plenty battery power to crank engine but no start. Leave it for a bit (10 mins)and it always starts.
I thought it might be related to an electrical component breaking down when hot , until this morning when for the first time the car would not start from cold (parked overnight).
I stress that this fault is rare and very random and was there both before and after the engine rebuild.
2.5 V6 Elite auto yr2000
Any ideas ?
Any help appreciated
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Paperclip test ... possibly a code 19 ?? (crank sensor ??)
http://www.omegaowners.com/forum/index.php?topic=90581.0
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First step is check for codes depending on the year either paper clip or pedal trick and post results. Quite possibly the crank sensor causing the non start, theres no rhyme or reason when they cause problems and can take months to go completely, Code 19 would signify this on a prefacelift.
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What they said. ^^^^^^^ :y
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Could it be an immobiliser fault? Just another idea to check, I think that it would show up as a flashing light on the dash during cranking when it fails to start.
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Done the paperclip test and only get 12 and 31 (start test and no rpm). bit worried now as if this is the cranksensor on the way out it could fail at anytime.
What next ??
:-\
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I would say that the symptoms are so indicative of the crank sensor failing that I'd be tempted to change it anyway. :-\
Have a look through the maintenance guide here: http://www.omegaowners.com/forum/index.php?topic=90540.0 (http://www.omegaowners.com/forum/index.php?topic=90540.0). If the sensor wiring is still routed up with the oil cooler pipes the chances are it's the original sensor and, by now, it will be on borrowed time if it hasn't actually failed. When it's replaced, the wire is generally routed up the inner wing so it's less susceptible to heat and also for ease of routing the cable.
I'm trying to remember if there's an obvious way to tell if the ECU is detecting cranking on the older ECUs. IIRC, the immobiliser light goes out during cranking, so, if this stays on while you're cranking with the fault present, it's a good indication of crank sensor failure.
Another thing to do would be to check for a spark during cranking. If there's not, it's a good bet that the ECU is not getting a decent signal from the crank sensor.
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Cheers Kevin
Will probably just get a new cranksensor.Any thing to look out for when shopping for one ? just go to VX dealer or are there any better buying options?
Cheers
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I had a similar issue a few years back with a cleo turned out to be a coil pack no mechanic just a thought :y
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Cheers Kevin
Will probably just get a new cranksensor.Any thing to look out for when shopping for one ? just go to VX dealer or are there any better buying options?
Cheers
Genuine GM is best in this case. They do vary, so, as it states in the guide, it's worth finding the connector on your current one and checking the type before picking one up from the dealer as they don't have a good track record of getting it right (and are often awkward when it comes to taking back electrical parts).
And also, IME, it's very rare for a coil pack to fail completely so the car won't start at all. Normally 1 or 2 cylinders are dropped as one of the 3 coils in the pack fails.
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Agreed kev the problem mec found for me or should I say suspicion was engine was heating pack up and wouldn't start pack changed worked great till went again few months later common issue with them apparently so as u can imagine replaced and sold sym1 else problem lol :y
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Oh another issue with another car mate was a dud battery would turn car over just wouldn't start it was weird blamed alarm dragging battery down and alsorts borrowed a bat for few days no pros new bat problem went lol try simplest oh and before someone shoots me down I'm no mec just from exsperance :)