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[JamesV6CDX]

Our flight arrived on schedule in Inverness at 14:25 yesterday afternoon, to collect a facelift Elite that was described as "mechanically perfect".


I'd taken a chance, and bought the thing unseen.. so I'm not grumbling... however, that description wasn't quite correct.

I'm not looking to moan, and have no intention of looking of recourse - I'm just after some opinions on fixing the damn thing.

First issue - drivers seat was right back, and wouldn't adjust. After spending an hour with various implements removing coins from the seat runners, I fixed that.  Ahh - ready to drive back at last!

First thing I noticed, was a misfire at idle. I now realised why the guy bu99ered off so quickly  knowing I had 650 miles to do in it.

Popped a lead off each side, tiny trace of oil but no contamination, they looked OK. Didn't have tools to investigate any further. I filled up with petrol and decided to do a few miles down the road to get a better picture.

At cruising speed - seemed OK! Just appeared to be missing at idle, and under load. I then decided nothing for it - will run the gauntlet for home. This turned out to be a bad idea 

I managed just shy of 400 miles - got from Inverness, down onto the M6.

I noticed during this time that the baffles must have let go in the exhaust - awful noise.

As I joined the M6, I noticed the fuel gauge appeared to have gone quite low, quite quickly. It went to red, and started flashing before I knew what had happend. Hmm.

Stopped at a garage. Revved the engine while outside the car - and it stank of petrol. Especailly at the rear. Had a look and couldn't really see any leaks.

It was misfiring - properly, at this time. Guessed it was unburnt fuel. Decided to take it to service area 17 miles down the M6, get some coffee and arrange recovery.

I put £40 of petrol in, and set off on the 17 mile run. As I took the petrol cap off to re-fill, there seemed to be a LOT of vapour type stuff coming out of the filler neck.

Drove on to next services - again, she seemed to cruise OK.

Bearing in mind I put in £40 - which took it to half a tank, it USED THE LOT, over 17 miles. Gauge flashing again, at the next stop 

 - now even if it's mis firing - this is like 2 miles per gallon - surely all that petrol couldn't have gone in the engine, over this time 

When I stopped again, I looked underneith, and the 2-4-6 side cat was glowing, absolutely red hot!!!

Is this pointing to a blockage - or is it unburnt fuel?

My thinking is, I will need -

Plugs
Lead check
DIS Pack
Good pair of cats
Eternalcar catback exhaust

Probably knackered the lambdas too.


Otherwise - the car's very nice 

Fixing the misfire I'm sure won't be a problem, but, I am thrown by the fact that SO MUCH fuel disappeared over 17 miles, with no trace of an external leak.

Opinions welcome, please 

[jonnycool]

Are you sure there's not a leak? You wouldn't use half a gallon a mile even if your foot was going through the floor! 

Hope you have better luck soon buddy 

Jon

[tunnie]

any air leaks around the plenum? Had that with 3.2 other day, o-ring got caught under plenum caused mis-fire and red hot cat.

[JamesV6CDX]

Are you sure there's not a leak? You wouldn't use half a gallon a mile even if your foot was going through the floor! 

Hope you have better luck soon buddy 

Jon

Positive.

Lie under it with engine running, shining a torch - can see no leaks around tank, fuel lines, or in engine bay. The exhaust, however, stinks of fuel, and it's all up the back window of the car.

I kid you not - £40 gone over 17 miles...  :-/

[jonnycool]

I think it's time to use a bit of your expertise and start dimantling things mate, Tunnie's suggestion seems a good place to start, and air filter etc.

And finding which cylinder is misfiring. Still wonder how so much fuel is being used though

Jon

[Andy H]

I put £40 of petrol in, and set off on the 17 mile run. As I took the petrol cap off to re-fill, there seemed to be a LOT of vapour type stuff coming out of the filler neck.

Normally the rear silencer doesn't get get terribly hot. If one cat was red hot is it possible that the rear silencer was unusually hot to & causing the fuel tank to get unusually hot?

Is it also possible that a hot fuel tank was venting your petrol onto the road?

What I'm trying to say is that poor running issues causing outrageous overheating over several hours on the motorway may have caused a vapour pressure problem in the tank which may never happen again.

[JamesV6CDX]

Still wonder how so much fuel is being used though

Jon

That's the one thing that is really puzzling me, and, is the stumbling block I have hit.

If it wasn't for this, I would have treated as basic misfire and diagnosed accordingly.

I guess all I can do, to quote MDTM, is fix the known issues, and take it from there...  :-/

Problem is, I now have a Nissan "Note", and my Miggy probably won't reach me for a few days 

[JamesV6CDX]

What I'm trying to say is that poor running issues causing outrageous overheating over several hours on the motorway may have caused a vapour pressure problem in the tank which may never happen again.

I had a simelar idea on the way back mate, but having been up for 24 hours can't get my head around it....

I'm guessing there was obviously extreme pressure in the tank, I thought this, when I saw the vapour.

I'm just a bit unsure as to how a misfire would cause it - the backbox didn't feel all that hot  :-/

[Markie]

Way out West....you could be looking at two different issues re that misfire. How bad are we talking misfire wise ( any more than norm for an Omega?)

[Omegatoy]

Hmm,
for what its worth!!!
I personally would go back to basics and do a full service including fuel filter, as a weak mixture will also cause hot cat and could well cause a missifre, untill you have caried this ot along with basic checks(coilpack leads etc and had a proper ;look its no good guessing at what the problem is! process of elimination by full service and checks should gove you a new perspective on it!!
  

[JamesV6CDX]

There was also a "whoosh" noise on accelerating, which sounded like an exhaust blockage to me... 

[joshwyatt]

Mmm, that is a shame James...I'm suprised by how many private sellers lie through their teeth when selling their car.

As Tunnie mentioned, on my 3.2 after a few minutes, if that, the cat was glowing red hot due to an air leak.

And I think you have every right to grumble, don't forget that you're mechanically aware...what would someone else think if they used that much fuel in 17 miles, and part of their exhaist was red hot? To them it'd be rather bad. They'd be straight on the phone to the seller. Not suggesting causing a fuss, but maybe let him know of the situation...he may feel obliged to offer assistance, be that maybe with £50 back.

I guess 3.2 cats won't fit a 3.0? Exhaust manifolds and other stuff is probably different? If they do fit, you're more than welcome to try my 3.2 cats on your 3.0 to see if that makes any difference.

[ballcock50]

One thing might be worth a look is it just one cat glowing if so check the plug leads on that side are connected to the correct plugs if not this will give you both the misfire at low revs and unburnt fuel inthe cat which will burn and make it glow. I know from experience after changing my rocker covers and getting them mixed up.

[JamesV6CDX]

I'm going to pop the plenum off tomorrow night and have a good old look

If that is the case, it would imply it's been bodged about with, and I will definately let the guy know what I found.

Moving on, however - I have got a couple of new cats on the way, new DIS, new LEADS, new plugs, new stat... so she's in for a treat 

[tango]

hi
from my own experience on a different car i would reckon its your ht leads not connected to the right plugs
this would cause a misfire and also make the exhaust hot to a point where it is glowing