Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: Webby the Bear on 07 September 2012, 09:47:27
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Hi guys,
2000 Omega 2.5 V6.
Noticed this a little while ago. The fuel gauge seems to be dropping real quick. Example: last night I filled up and had just over half a tank. when I drove to College this morning my fuel gauge was just over half a tank so thats fine. I then noticed that about 2 miles down the road that it had dropped to just below half. I checked the trip computer and I watched the range full very rapidly during this morning's journey: started at 215 and kept dropping. but then it's now seemed to slow down around the 165-170 mark. now my trip involves a dual carriage way trip and in the past as soon as it gets on a motorway or national limit road the range starts to increase. but again it kept falling.
i've had a look uner the car while it was running and there are no visible leaks at all. is it worth popping a spark plug out to see if its soaked with fuel?
any ideas?
cheers
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Remember that the trip computer takes an average over the last x miles (15 or so I think) for it's calculations... I can easily take 100 miles off the range in just a few if I come from a sensible cruise to blatting around the twisties ;)
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cheers LD.
Yeah to be honest it wasnt so much that that bothered me. it was the drop over a very short distance on the fuel gauge. i certainly can't see any leaks or smell petrol anywhere.
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Petrol will evapourate quickly when it leaks.
If your journeys are now shorter, expect to use more, but if its a sudden drop in MPG, and nothing has really changed, I think you need to investigate further.
The MID is not a good test for this, but the gauge should be.
I went out yesterday lunchtime for LPG - it was pretty damn empty, the (petrol) range started at about 420m (yeah, its got the wrong config on the GID, and I can't be bothered to reconfig it ::)), and by the time I'd filled up (bearing in mind I'd used little petrol, as mostly on gas), it was 220m range...
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Sounds normal to me . . . ???
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Thanks guys,
TB, yeah it's exactly that... we're used to low MPG as we do short trips but this is a ''noticeable'' drop of the range AND on the petrol gauge.
Sorry what is MID and what tests could I conduct to isolate a leak? :) If it does have a leak and it's in the injection area at least I have a spare fuel rail :)
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Can you smell petrol inside the car when your driving :-\
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MID is the screen above centre airvents
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cheers guys. nope ive already tried to sniff for petrol and nothing. as said ill pull a plug out, check it for being soaked. ill recheck for visible leaks and check the fuel filter too.
anything else i can do? :-\
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Be interesting to see if the trims have gone haywire. Passing Brackley soon?
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our mv6 was loosing fuel alarmingly ..turns out the "new" fuel filter we fitted had a leak on the seam...could be worth while checking that?
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Be interesting to see if the trims have gone haywire. Passing Brackley soon?
What does that mean ? :)
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cheers guys. Yeah ill definitely be checking the fuel filter. Sorry TB what seems? I'm actually up your way in October for the silver stone BTCC. 29 quid for a day ticket :-) cant wait :-)
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edit. Trims not seems. Sorry lol
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(http://i15.photobucket.com/albums/a384/themarbleintheoatmeal/smilies/watchdrama8jm.gif)
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Hi guys,
not bumping but just spoke to me old dear. she says the fuel is definitely coming down very quickly so i believe there is something wrong.
i've checked the underneath while car running and no visible leaks. ill check the fuel filter next.
i've also checked spark plug 1 for a wet end but then i thought ''hmmm doesn't each cylinder get it's own fuel injector''? therefore i really need to check each plug for wet electrode???
if i find a wet plug can i simply just replace the fuel rail as i have ralf's one sitting in ze garage?
cheers guys, your help is appreciated :)
:y :y :y
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Hi guys,
not bumping but just spoke to me old dear. she says the fuel is definitely coming down very quickly so i believe there is something wrong.
i've checked the underneath while car running and no visible leaks. ill check the fuel filter next.
i've also checked spark plug 1 for a wet end but then i thought ''hmmm doesn't each cylinder get it's own fuel injector''? therefore i really need to check each plug for wet electrode???
if i find a wet plug can i simply just replace the fuel rail as i have ralf's one sitting in ze garage?
cheers guys, your help is appreciated :)
:y :y :y
If your plugs were wet with fuel you would have other running issues and probably a knackered cat by now,is the car running normally?
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yes mate car is running lovely and no misfire or any other problem
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right then chaps. I've had a word with my tutor (beauty of being in motor vehicle school lol) and he said that if I've got no visible leaks (which i haven't) and no smell of fuel and nothing else obvious that i should check spark plugs but not for wetness like i thought. But for soot as that will show a richness. Now that's interesting cos when i pulled plug one it was black. I thought this was normal? So I'm thinkin i need to replace this injector rail? However he did mention a sensor that i cant remember what he called it that keeps the engine's computer thinkin the car is still cold therefore uses more fuel. SO before i go ahead and replace fuel rail anyone know what this sensor is he was talkin about and the likelihood of it being this? Sadly i caught him on break and he had to attend to other things so anything you guys can help me with would be awesome :-) x
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He was talking about the coolant temperature sensor - of which there are two, one runs the gauge and one talks to the ECU.
To find out if that's reading wrong you need to get live data off with something - tech2/hand held scanner etc - and see if it's reporting sensible values to the ECU (i.e. >80C or so when up to temperature)
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thats the one! great stuff. Cheers Aaron. So a logical set of questions now would be how easy are these to replace if faulty? And are these likely to fail and go bad?
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I seem to recall it's on the coolant bridge between the heads on the Omega, which makes it a little trickier to get to (plenum etc off) but not too bad.
They do go bad - certainly on other cars - not sure on the Omega but you've reminded me to check mine again as my economy seems to have suffered something chronic recently!
Another thing to check would be the MAF readings on live data; both air volume and inlet air temperature, as both will directly affect fuelling. Someone 'in the know' (like Kevin/TB/etc) would probably know if the values looked 'about right' by eye.
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As said worth checking temp sensors are good,if yours is a 2.5 you are lucky as inlet air temp sensor is seperate,on the 2.6/3.2 its part of the MAF,don't worry about the single wire sensor for the gauge as that one has no bearing on how the engine runs :y
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Don't be too hasty to condemn it for sooty plugs. If the engine is cut straight after a spirited drive, I'd expect them to be clean. If it's done any idling, or been mimbling around town, I'd expect them to be sooty as they simply don't have enough heat in them to prevent a light layer of carbon build-up.
IME, fuel injector problems are very rare. It might be over-fuelling for other reasons, though. Have you got an exhaust gas analyser there? Worth a check to see what's coming out of the exhaust?
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Thanks guys.
here's a pic of the engine minus the plenum and inlets..... is the temp sesor visible here? if so can you tell me where it is and is it possible to see a dodgy sensor by eye?
(http://i1226.photobucket.com/albums/ee402/webbybear1/Camcovers.jpg)
thanks again. ill defo book in a tech 2 check with one of the legends... hopefully TB if he's free :) :) :) :) :-* :-* :-*
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Bring it over.
Coolant temp sensor at back of V on coolant bridge (bridge between 2 banks)
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thanks so much guys. Pm sent to TB :-)