Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: D on 13 September 2014, 00:46:43
-
Well at least transiently. Ran out of LPG around half a mile from the pump, switched over to petrol (1/4 tank), spluttered, misfired and then died. Filled up with petrol and gas. Cranks, but does not start on petrol. Forced start on LPG, and she fires up and runs.
Now I have to sort out this mess before Monday and then drive 250 miles down the M1.
What a pain. What do you think? Fuel pump blocked due to a lowish fuel level(crud) or just plain dead? Have a misfire code on cylinder 1 and a pre-cat error code. I cannot imagine the misfire will prevent the engine from starting up at all.
-
What are the exact codes?
-
0301 and 0420. At least thats what I think it was. I was a bit cold and miserable and had a cranky child to contend with. Will re-check in the morning.
-
Could be stale fuel... When did you last put petrol in it?
Also, has it had a crank sensor yet? Rarely shows a code...
-
Do you have the facility to check the trims - in case LPG has thrown the trims way off to make them invalid for hot petrol running.
-
Unlikely to be stale fuel. Last filled up about 6-8 weeks ago. Plus I have topped up to half a tank again.
No chance of looking at trims.
Crank sensor is original I guess. No mention of it being changed in the past records. But would crank sensor fault allow running on LPG? Would it not affect that as well?
-
Unlikely to be stale fuel. Last filled up about 6-8 weeks ago. Plus I have topped up to half a tank again.
No chance of looking at trims.
Crank sensor is original I guess. No mention of it being changed in the past records. But would crank sensor fault allow running on LPG? Would it not affect that as well?
I think, the crank sensor only switches on the fuel pump once the engine is running. Starting is done using residual pressure in the fuel rail whereas lpg is supplied as long as there is fuel (pressure) in the tank and both cut off valves are open.
If either the fuel pump or the crank sensor are playing up, it will never start on petrol...
-
And how do I differentiate? Which reminds me I need to check the relay as well.
-
Unlikely to be stale fuel. Last filled up about 6-8 weeks ago. Plus I have topped up to half a tank again.
No chance of looking at trims.
Crank sensor is original I guess. No mention of it being changed in the past records. But would crank sensor fault allow running on LPG? Would it not affect that as well?
I think, the crank sensor only switches on the fuel pump once the engine is running. Starting is done using residual pressure in the fuel rail whereas lpg is supplied as long as there is fuel (pressure) in the tank and both cut off valves are open.
If either the fuel pump or the crank sensor are playing up, it will never start on petrol...
Nah.
A failed crank sensor is a failed crank sensor, the petrol injectors won't fire, thus LPG piggyback systems won't fire either.
-
Yep, and the petrol pumps do prime before cranking on the 3.2.
-
Ah ok wrt crank sensor :y
Was told different when I asked about fuel pump priming on switching a couple of years ago :-\
That said, even if the pump primes, if it's on its last legs, the pressure won't be great.
-
Are you sure/could it be that, it didn't run out go lpg, but died due to crank sensor fault.
Is it worth flicking back and forth between fuels to confirm its defo only petrol at fault?
If it does prove to be petrol only, when was fuel filter last changed?
Is the eml bulb working, does it illuminate at ignition on? ....although, you don't mention a fuel trim code. Then again, 0301 would of bought the eml on, then reset on re start if the fault cleared.
More questions than answers, but does look like a petrol system fault from what you said. :-\ ....IMO.
-
Right, ran out of LPG, switched to petrol automatically, car spluttered and died.
Now that I have topped up both petrol and LPG, it dies on switching to petrol and refuses to fire up on petrol. Force an LPG start (ie hold LPG switch down and crank) and the car fires up. The EML is on, codes as above.
So I can potentially run on LPG all the way back down south.
No clue when fuel filter was last changed. Full Vx service was 2 years ago, presume it was changed then. Not certain though.
-
If you get it running above idle - say a steady motorway cruise, does it still drop dead if you switch to petrol?
If so, I'd say it's fuel pump related (is the fuse OK?).
If it can be made to run on petrol in this way, maybe fuel trims have gone badly enough awry that it won't idle on petrol.
Doesn't sound like crank sensor to me. It wouldn't start on LPG if that had died.
-
I have to say I did not try that, just wanted to get home and was worried about loosing power steering assistance. Let me give that a go tomorrow.
Could a badly blocked fuel filter cause this issue as well. May be worth changing that first.
-
No clue when fuel filter was last changed. Full Vx service was 2 years ago, presume it was changed then. Not certain though.
Visually check it - it'll look brand new if less than 2years old....
-
With it being my last day of leave today, it has been impossible to do anything useful. However on rechecking the codes it now throws up a 0170 and 0173.
If the filter looks old, I will change it as a first step. Managed to get the car started again today on a forced LPG start, but tried what Kevin suggested although it was more like 30mph and the car just died on switching to petrol. Do not want to try that at higher speeds due to the fact that I cannot get it going again till I pull over and then force restart the engine on LPG.
-
Try it with the MAF unplugged :-\
-
With it being my last day of leave today, it has been impossible to do anything useful. However on rechecking the codes it now throws up a 0170 and 0173.
If the filter looks old, I will change it as a first step. Managed to get the car started again today on a forced LPG start, but tried what Kevin suggested although it was more like 30mph and the car just died on switching to petrol. Do not want to try that at higher speeds due to the fact that I cannot get it going again till I pull over and then force restart the engine on LPG.
0170 0173 = Fuel trim malfunction banks 1 and 2. The fuelling is off, but the question is why? If its spent more time on lpg than petrol, which it undoubtedly will have, then that would suggest the lpg has pulled the fuel trims far enough away from zero to throw a code.
But difficult to tell further without diagnostics. Maf would show a fault on gas as well. Assuming the fuel trims are not a result of the petrol issues but a cause. :-\
-
Maf came from a google as a possible cause for over fuelling, giving P0170/3, admittedly on an X18SE Astra... :-\
The other thought was if the vacuum line from the fuel pressure regulator to the throttle body has come adrift, would that affect lpg running?
-
Given that its running LPG, and has trim codes, I'd be inclined to believe the LPG has pulled the trim out too far.
If you have access to a code reader that can reset codes, try resetting them, on DBW engines, that also resets the trims.
What make LPG is it?
-
Will try that.
Its an AEB based system called Emer (http://www.emer.it/).
-
And its back and running again. Turned out to be a relay, new one in and all seems to be fine in Omega land. Thanks to Al for sorting it out. Although Al does seem to have a weird user name nowadays. ???
-
No problem :y Glad it's back to its normal self...
As for the name, if the cap fits and all that ::)