Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: jimbo_lad on 28 December 2011, 18:21:34
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Hi Folks
I bought my Elite Estate 3.2 V6 in Aug 2006 and I’ve been a member of this forum since then. I haven’t posted much, but have often looked at it and found it interesting and informative. Current mileage is 86k.
However issues are beginning to accumulate.
Two years ago the Power Sounder kept going off which, with help from this forum, I diagnosed as a failing battery in the sounder itself. Having sourced a replacement for this unusual battery, I was about to solder it into the existing unit, when I read here about the potential serious fire risk associated with old circuit boards in this unit. The circuit board was showing signs of “tracing”, so I decided to disconnect the Power Sounder permanently, rather than repair. So that issue is sorted.
Pre Cats
Over the past 18 months the Exhaust Management Light has come on from time to time (usually a few months). The Pedal Trick revealed codes 0420 and 0430. Kevin Wood’s description of these codes and Catalytic Efficiency in the FAQ section were very helpful. The indication seems to be the Pre Cats are failing, but this doesn’t matter much so long as the main cats are OK – which they seem to be since the car passed MOT last April. So I'm ignoring this for now.
Falling Fuel Consumption
However the main unresolved issue is fuel consumption, which has fallen badly over the past 12 months. I used to get at least 32 mpg on a long steady run, but now only get about 24 under identical conditions with the same driving style. MPG on shorter local journeys has fallen from 26 to 20 mpg.
The engine continues to start easily and run smoothly, although it now changes up through the gears more slowly. Running temp is around 85 deg, typical for the V6, and it doesn’t warm up any faster – so thermostat probably OK.
Tyre pressures are OK and it has been serviced regularly at main dealer.
The EML light came on again last Sept – codes 0420 and 0430 again present This time I booked it into the main dealer to look into the poor fuel consumption. The day before the booking I fuelled up and , by mistake, put in Premium 4 star. The EML went out within 5 miles – interesting, but could be a coincidence. I told the garage about the codes and emphasised I didn’t think this was associated with the poor fuel consumption – but they are the experts so I would value their advice. Needless to say I left £50 poorer and none the wiser. They found codes 0420 and 0430 as I knew they would and had nothing to advice on the poor fuel consumption. “Bring it back if the light comes on again”
The light came on again in early Dec and codes 0420 and 0430 again present (plus 1613 due to missing Power Sounder). This time Premium fuel hasn't cleared the light, and even if it had I doubt if the fel consuption would improve since it didn't last time.
Yesterday I added some Redex Premium fuel additive – its supposed to help clean jets/valves/cylinder head etc – not sure if its likely to work and too soon to tell – however it might be more effective than another trip to the main dealer!
Could the codes 0420 and 0430 be associated with poor fuel consumption? Any thoughts on this, and what else to do would be gratefully received - I'd like to get to the bottom of this and improve fuel consumption.
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What about the standard service items? When were they last changed?
* Air Filter
* Fuel Filter
* Breathers
* Plugs
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Initially check the condition of the air filter and plugs. Then check standard service items. Don't assume the dealer does the job properly, Vauxhall dealers are universally either incompitent or fraudulent.
If that doesn't show anything up, might be worth visiting Keviin Wood in Alton, to check it over with Tech2 (he'll know more than dealers).
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Thanks to Tunnie and TheBoy.
Service in April 2011 was intermediate, so last full service was Apr 2010 - when plugs/air filter/fuel filter all changed (at least that's what the invoice shows!). However I've only done 10k miles since then, so they should be OK, though I guess you never know?
I've checked the Air Filter and its a clean as a whistle.
By breathers, do you mean cleaning the V6 Crankcase breather set up?
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Thanks to Tunnie and TheBoy.
Service in April 2011 was intermediate, so last full service was Apr 2010 - when plugs/air filter/fuel filter all changed (at least that's what the invoice shows!). However I've only done 10k miles since then, so they should be OK, though I guess you never know?
I've checked the Air Filter and its a clean as a whistle.
By breathers, do you mean cleaning the V6 Crankcase breather set up?
Yup!
Check the fuel filter, you can tell by looking its rough age. Bet thats not been changed!
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Timing OK?
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Thanks, Tunnie - I'll get under the car tomorrow and see what I can make out. Should the label give an indication of age?
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Thanks, Tunnie - I'll get under the car tomorrow and see what I can make out. Should the label give an indication of age?
Just look at its general condition, photo would paint 1,000 words :y
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Checked out the fuel filter earlier today - here's a photo:
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1933Medium.jpg)
Seems in pretty good condition consistent with having been changed in Apr 2010. I would change it anyway if I had axle stands and suitable jack - but since I don't I've moved on to look at breathers and spark plugs.
I've just removed Plenum and will clean tomorrow. This is what it looks like on removal from the car:
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1949Medium.jpg)
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1950Medium.jpg)
These don't look too bad, but we'll see more when I dismantle and clean tomorrow!
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Yup, looks honest enough so far :y
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Hi - It may be worth checking the handbrake cables - mine had corroded inside the plastic sleeving and therefore were not releasing the shoes fully, pretty unoticable apart from the fuel consumption as there was still a little bit of drag. My handbrake still worked fine and I was unaware of the problem until my garage found this issue when they were doing the rear brakes. Once fixed I found the car was nippier and the average consumption went up and I was getting around 25mpg with some town and motorway driving.
Regards
Darren
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Thanks, Darren - I'll check that as well.
Meanwhile I've spent the morning cleaning the Plenum. I was a bit disappointed it was relatively clean - here is the inside of the Throttle body and Plenum before cleaning:
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1955Medium.jpg)
However one of the pipes on the breather bridge was well blocked with pale brown emulsified oil - see below:
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1954Medium.jpg)
We used a novel way of cleaning this narrow tube - started with pipe cleaners then used a syringe to squirt carb cleaner through under pressure - worked a treat - see video clip showing third squirt:
http://s1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/?action=view¤t=MVI_1971.mp4 (http://s1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/?action=view¤t=MVI_1971.mp4)
Hopefully cleaning this will make a real difference -time will tell. Does anyone know what this tube actually does? (its the narrowest of the 4 tubes at the rear of the Plenum and goes down the rear of the engine on drivers side).
One other thing we noticed was the fact that the plenum differed from the version shown in the maintenance guide. My car (2001 vintage) has the extended 2 part breather bridge (mentioned in the guide as a later variation to the 2003 engine
described). However, my model doesn't have the vent housing shown in the guide and instead has the assembly shown in the second photo above. We took this apart and cleaned - it wasn't very dirty and there weren't any breather holes of the type shown in the guide - unless I've missed something?
Now need to reassemble and test.
Thanks for the help so far - I'll keep you posted on progress.
Jim
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Thanks, Darren - I'll check that as well.
Meanwhile I've spent the morning cleaning the Plenum. I was a bit disappointed it was relatively clean - here is the inside of the Throttle body and Plenum before cleaning:
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1955Medium.jpg)
However one of the pipes on the breather bridge was well blocked with pale brown emulsified oil - see below:
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/IMG_1954Medium.jpg)
We used a novel way of cleaning this narrow tube - started with pipe cleaners then used a syringe to squirt carb cleaner through under pressure - worked a treat - see video clip showing third squirt:
http://s1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/?action=view¤t=MVI_1971.mp4 (http://s1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/?action=view¤t=MVI_1971.mp4)
Hopefully cleaning this will make a real difference -time will tell. Does anyone know what this tube actually does? (its the narrowest of the 4 tubes at the rear of the Plenum and goes down the rear of the engine on drivers side).
One other thing we noticed was the fact that the plenum differed from the version shown in the maintenance guide. My car (2001 vintage) has the extended 2 part breather bridge (mentioned in the guide as a later variation to the 2003 engine
described). However, my model doesn't have the vent housing shown in the guide and instead has the assembly shown in the second photo above. We took this apart and cleaned - it wasn't very dirty and there weren't any breather holes of the type shown in the guide - unless I've missed something?
Now need to reassemble and test.
Thanks for the help so far - I'll keep you posted on progress.
Jim
Is it the gearbox breather I've read about?
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Er no, where is a gearbox mentioned? ???
As mentioned in what you quoted its the breathers from the plenum!
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That's a big mpg hit and I'd be surprised if you could lose that much energy in binding brakes and not notice the smell or the boiling fluid.
Is yours an auto? If so is it using top gear?
Just a thought...
BTW your intake is exceptionally clean IMHO.
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Chris - thanks for your comments.
Handbrake
I agree it seems unlikely that brakes could cause that much extra fuel consumption, but worth checking out - there are lots of historical posts about corrosion to hand brake cable. When I first jacked the car up, I thought there was a bit of an issue; however after taking the wheel off it was clear the handbrake cable was moving freely and the slight resistance seems to be due to differential and very slight brushing of brake pad on the disc (the car hasn't been out for a week and I guess in this warm weather there's some very slight corrosion to the discs). When I road test I'll check the temp of the drum and disc to make sure this isn't a problem.
Auto Gear box
One thing I had rather forgotten about was the very slight oil leak reported by the main dealer when they tried to fix the petrol issue last September. The mechanic told me it was easy to top up, so I bought a litre of fluid, but haven't yet topped it up. However looking at the maintenance guide it doesn't look easy at all, given I don't have a proper jack or axle stands.
Chris to answer your specific question - the car does get into top gear, but recently has tended to change down sooner than it used to - I've assumed this was due to lack of engine power rather than a gear box issue. However it would be good to top up the fluid - can anyone tell me whether this is possible without axle stands?
Engine Issues
I finished the work on the engine yesterday and very pleased it started first time. Most of the plenum/tubes were surprisingly clean (for 86k miles), but as mentioned in earlier post, one of the tubes was blocked - so I'm hoping this will make a difference. I also changed the spark plugs (the old ones were rather dirty - not completely sooty, but not good).
Next step is to take it for a decent road test and see what mpg I get.
BTW this is the first time I've done any serious work on engines since 1976 when I stripped down a Rover 2000 engine and put in new pistons and big ends, as well as grinding in valves etc. Unfortunately I didn't get to enjoy that car for long since around Xmas that year a young kid stole a car just up the road on the way to school. He was keen to show off his Graeme Hill impression to his mates - unfortunately, while he knew what to do with the accelerator, the same wasn't the case Re brake pedal. He came down a slope towards T junction, went straight over and smashed into both my car and my neighbour's writing off all 3. He ran away while his mates watched. Despite all the witnesses, Police were unable to find out who he was (something to do with interviewing minors).
I also had earlier experience with pistons on an A35 van - but that's another story........
Jim
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This issue has been resolved in a most surprising way.
After the work detailed in earlier posts there was no improvement in fuel consumption and I was getting quite depressed - so much so that I started looking at a replacement and have more or less settled on a Skoda Octavia. Last night I started looking at a Skoda forum and found several posts about poor fuel consumption. One comment caught my eye - "is your car recording miles per US gal?"
A quick check revealed mine was indeed set to US settings! I'm not sure whether to laugh or cry!
Having reset, I made a short 10 mile journey this morning and recorded 24mpg from a cold start, and on return an hour later when car was still a bit warm I got 27.5mpg. Much the same as I used to get and pretty good for a 3.2 on a short run.
It seems I accidentally changed the settings to US more than a year ago - there never was a problem.
With hindsight, I should have checked mpg in the old fashion way, rather than relying on the electronics. Too much electronics in these modern cars!
Am I the only person to have fallen into this trap (I couldn't fine any earlier references)?
You live and learn.
Jim
PS a US gal is 80% of an imperial gal. So the 24miles per US gal mentioned in my first post is equivalent to 30 miles per imperial gal
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How do you check what setting it's on and how do you change it?
I've noticed my consumption droppping slightly over the past few months (but this could be due to other issues).
Thanks
Tim.
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Its deep in the systems settings menu - page 36 in my manual
(http://i1091.photobucket.com/albums/i398/jimbo_lad/Omega%203_2/Omegasystemsettings-units.jpg)
Jim
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This issue has been resolved in a most surprising way.
After the work detailed in earlier posts there was no improvement in fuel consumption and I was getting quite depressed - so much so that I started looking at a replacement and have more or less settled on a Skoda Octavia. Last night I started looking at a Skoda forum and found several posts about poor fuel consumption. One comment caught my eye - "is your car recording miles per US gal?"
A quick check revealed mine was indeed set to US settings! I'm not sure whether to laugh or cry!
Having reset, I made a short 10 mile journey this morning and recorded 24mpg from a cold start, and on return an hour later when car was still a bit warm I got 27.5mpg. Much the same as I used to get and pretty good for a 3.2 on a short run.
It seems I accidentally changed the settings to US more than a year ago - there never was a problem.
With hindsight, I should have checked mpg in the old fashion way, rather than relying on the electronics. Too much electronics in these modern cars!
Am I the only person to have fallen into this trap (I couldn't fine any earlier references)?
You live and learn.
Jim
PS a US gal is 80% of an imperial gal. So the 24miles per US gal mentioned in my first post is equivalent to 30 miles per imperial gal
Fantastic. What a result! and it's not as if you've been paying over the odds while the "problem" existed.
You're right about electronics in cars (but more specifically automation within cars). There's no substitute for sporadic checks by independent means and also the ability to disable options by the superior human.
From and electronic engineer.
Well done by the way. And thanks for the reminder. :y
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Well done Jim I enjoyed this read :y