Fuel Consumption problem all of a sudden

[Oakley 0]

Hi All

 

I think I need advice yet again with my VR6. I have been getting great fuel consumption since I got my C (about 32mpg average) I did a full tank on the motorway and got about 435 miles to the tank but I let the fuel run right down below reserves.

 

Now I have filled up againb and am getting about 25mpg on the motorway instead if the usual 34mpg. Anybody have any ideas.

 

Also another symptom all of a sudden and something that just started. My C is sometimes just stalling when I put my clutch in. It started the other day but yesterday was the worst because I pulled into a furniture shop and when I came out and started my C, it stalled and sounded just like it does when the car is running out of fuel. Tried again and again the same thing. Third attempt was more successful with a nice high rev. Does anybody have any ideas?

 

Oakley

[Oakley 0]

AAAAAAAAAAAAAAH. Just went out for 2 hours and now it is worse. I had to free wheel into the burger king because it stalled again and would not start.

 

Is it possible that a loose back box could cause the C to stall and chew fuel?

 

Anybody PLEASE!!!

 

*very quiet for a change* any Mods about to help with the probles?

 

Oakley

[tonytiger 0]

Do you have access to vagcom to check the diagnostics? I suspect it won't show anything, but it's always a good place to start. If you don't have vagcom yourself, I'd strongly recommend it (along with the bentley manual) - in my experience it will pay for itself far quicker than you might expect.

Have you searched the forum for similar problems? I had a very bad spell during the summer in my vr, got as bad as 20 mpg average from a tank - was suggested this was lambda sensor related - still don't think I've realy got to the bottom the problem. Other suggestions would be fuel filter, dying fuel pump, coil pack, leads, but I'm sure somebody better qualified than me will have a more specific idea as to what the problem may be. Sorry I can't be more help.

[Oakley 0]

Lo again

 

Apparently the Vag reported that my Oxygen sensor was failing and my Lamda sensor has intermittent problems. Could these be causing my issues I wonder?

 

Oakley

[Reggit 0]

Having just had VAGCOM on Oakleys car, it reports Lamda sensor intermittent and oxygen sensor (g39) - No signal. Codes where then reset.

 

Took car for drive and immediatley the error

 

00525 Oxygen Sensor (G39) - No signal

 

returned.

 

Would this cause Oakleys problem, where is this sensor located (thumbing through Bentley manual at minute!), and is it easily possible to check supply voltages before replacement.

 

Sorry for all the questions.

[Banana Man 0]

I was going to say it could be the lambda its located at the bottom of the downpipe about 12" back from the back of the subframe easy enough to get to but can be a ba*tard to undo it's a 24mm spanner job iirc

[tonytiger 0]

Yes, no signal from the lambda sensor would definitely be a problem. Could be worth looking for any obvious wiring problems before replacing the lambda though, as it'll cost around £60 for a replacement.

[Oakley 0]

Once again, Thanks Reggit for coming out. I think I need to replace both parts unless the Lamda IS the 02 Sensor in which case it will only be 1 part. Any ideas as to where I can aquire this?

 

Banana Man, what does this Lamda actually look like and what exactly is the subframe?

 

Reggit, sure you dont wanna sell me your leather?

[Oakley 0]

Tony Tiger, do you know where I can get a origional Lamda? Price is never an issue when it comes to the C so the better the part, the better if you know what I mean. Tonytiger, would this definately cause fuel consumption problems and can they break that easily. Is it just age?

[Banana Man 0]

Oakley If price isn't an issue go to the stealers and order a B021 906 265E that is the original part number for the lambda sensor ( 02 sensor) a dead lambda sensor will definately cause fuel consumption oproblems as that is what tells the ecu how much fuel to feed the cylinders with. Just like anything with age they wear out if VAG COM says it's dead it probably is LOL

[tonytiger 0]

Oakley, as Banana Man says a dead sensor will cause problems - a new one from VAG has a list price of £72 + vat, but you should be able to get 10% or more discount (parts club price is about £62) - if your local stealer won't give you a reasonable discount try another one. And yes, O2 / Oxygen / Lambda are just different names for the same thing - confusing isn't it?

 

When I had errors from the lambda sensor, it wasn't just a straight forward 'no signal' problem, so replacing the lambda in my case didn't really solve the problem - in fact, I don't there was anything wrong with the sensor in the first place. If you're interested, this thread is about the problems I had.

 

I'd also really recommend fitting an AFR (air fuel ratio) meter as this will allow you to monitor the output from the lambda. See this thread as good starting point.

[Oakley 0]

Thanks all.

 

Tonytiger, apparently you have access to the parts or you work for gs+f. Is that correct because if so, I would like to order the part required and prefer to get it from someone here than a stealer. Moral thing and all!

[tonytiger 0]

No, I don't work for gsf / ecp / vag - it's just that I've recently had a new lambda fitted on may car (and checked the parts club price list too). I've also spent about £700 just on parts from dealers over the past year - and have found some give better discount than others. Not sure how long you've had the car, but I'd expect that at best you'll need a new vag part every one or two months - in my case I've averaged one visit to the dealers per fortnight over the past year!

 

It's always worth looking at the parts club price list (should be avilable somewhere else on this forum) - the discount varies from part to part but can be as much as 30%. This will give you some idea as to how generous you can expect the dealer to be. Also, policy varies dealer to dealer but one of my local ones told me that they always want to make at least 10% profit on each item so they are sometimes limitied in the discount they can offer.

[Oakley 0]

Seems to me that your C sounds to be in good condition with all the parts you have been buying. Do you know where on the Forum I can find the parts list?

 

Thanks Tonytiger

[Ford 0]

Need to join the Corrado Club to benefit from parts club. Check out servicing and suppliers section for parts sticky.

[Oakley 0]

Thanks ford, I will have a look! and join the Corrado Club to.

[Oakley 0]

Just ordered new Lamda sensor for £75 from stealers. as well as front and rear pads, damned stealers ripping me off again @ nearly £100 just for pads!