[Steve Webb]

Haynes Manual 🙂

[Steve Webb]

Haynes Manual 🙂

[Steve Webb]

Well, as per my previous posts I was having a high fuel consumption issue. Just town driving was giving a return of 19MPG.

These are the things I’ve done so far which to be honest didn’t have any impact…

Exhaust leak test – Visually and aurally by me including a ”marigold” test (marigold on exhaust pipe to check for pressure. Also for a fiver I got an emissions test inc. them looking for exhaust (specifically manifold area) leaks. All good.

Vacuum leak test – This was a bit hit and miss because you can’t really get in to all the places you need to with the carb cleaner. BUT there was no leaks in the places I could get to.

Voltage leak test – Done in the dark to see if there were any sparks or ”arcing” between the HT leads. Again, I couldn’t find anything.

Stuck caliper checked for. Put car in neutral and rolled. No resistance at all.

Cleaned EGR – Performance seemed to increase slightly but nothing really noticeable.

SO…..

I was constantly checking fuel consumption with no improvements at all. THEN….

I decided that as I had a spare MAF sensor (from a previous car of the same make/model) and as my reading from my last scanner data was low (9 kg/hr) I took my electric contact cleaner and virtually emptied half a can spraying the sensor and it’s connector… left it to dry for about a week in the garage, stuck it in and immediately noticed what I believed to be an increase in power.
Checked consumption today using the brim to first click method and what do you know, with no change in type of driving …… 25.6MPG

I’m still going to do the other things that have been suggested like swap out the Disspac as I have a spare one.

BUT at least I now have hard evidence of very good improvement. I’ll keep checking consumption but I’m going to call this done

Cheers to everyone for ALL your help

[Steve Webb]

Well, as per my previous posts I was having a high fuel consumption issue. Just town driving was giving a return of 19MPG.

These are the things I’ve done so far which to be honest didn’t have any impact…

Exhaust leak test – Visually and aurally by me including a ”marigold” test (marigold on exhaust pipe to check for pressure. Also for a fiver I got an emissions test inc. them looking for exhaust (specifically manifold area) leaks. All good.

Vacuum leak test – This was a bit hit and miss because you can’t really get in to all the places you need to with the carb cleaner. BUT there was no leaks in the places I could get to.

Voltage leak test – Done in the dark to see if there were any sparks or ”arcing” between the HT leads. Again, I couldn’t find anything.

Stuck caliper checked for. Put car in neutral and rolled. No resistance at all.

Cleaned EGR – Performance seemed to increase slightly but nothing really noticeable.

SO…..

I was constantly checking fuel consumption with no improvements at all. THEN….

I decided that as I had a spare MAF sensor (from a previous car of the same make/model) and as my reading from my last scanner data was low (9 kg/hr) I took my electric contact cleaner and virtually emptied half a can spraying the sensor and it’s connector… left it to dry for about a week in the garage, stuck it in and immediately noticed what I believed to be an increase in power.
Checked consumption today using the brim to first click method and what do you know, with no change in type of driving …… 25.6MPG

I’m still going to do the other things that have been suggested like swap out the Disspac as I have a spare one.

BUT at least I now have hard evidence of very good improvement. I’ll keep checking consumption but I’m going to call this done

Cheers to everyone for ALL your help

[Steve Webb]

Thanks for the vid.

I actually took it to a shop who offer exhaust checks for free so they have done some tests and no leaks apart from one small one near the back box which they’ve kindly filled for free… I presume being just behind the back box this couldn’t affect the fuel economy being that far past the O2 sensors??

Anyways I’ve also tried to re-do a vacuum leak test using the carb cleaner method and also using a length of hose to listen for ”squeals” from vacuum leaks. The trouble is my intake manifold is the plenum style and there’s simply no room to get the carb cleaner where you want it or indeed get the hose to where you want it either. There is also (due to the positioning of the plenum) nowhere to hook a vac gauge up to.
The only method I’ve seen done is the ”smoking out” method using a cigar. Does this work? I’ve seen Scotty Kilmer’s vid on it…
http://www.youtube.com/watch?v=zMok2y05jNE
…but I would have thought you’d have to feed the smoke in under pressure? Any ideas/experiences of this?

If not I’ll have to be satisfied thus far and move on to the other things on my list to check.

Cheers guys.

[Steve Webb]

Thanks for the vid.

I actually took it to a shop who offer exhaust checks for free so they have done some tests and no leaks apart from one small one near the back box which they’ve kindly filled for free… I presume being just behind the back box this couldn’t affect the fuel economy being that far past the O2 sensors??

Anyways I’ve also tried to re-do a vacuum leak test using the carb cleaner method and also using a length of hose to listen for ”squeals” from vacuum leaks. The trouble is my intake manifold is the plenum style and there’s simply no room to get the carb cleaner where you want it or indeed get the hose to where you want it either. There is also (due to the positioning of the plenum) nowhere to hook a vac gauge up to.
The only method I’ve seen done is the ”smoking out” method using a cigar. Does this work? I’ve seen Scotty Kilmer’s vid on it…
http://www.youtube.com/watch?v=zMok2y05jNE
…but I would have thought you’d have to feed the smoke in under pressure? Any ideas/experiences of this?

If not I’ll have to be satisfied thus far and move on to the other things on my list to check.

Cheers guys.

[Steve Webb]

Hi guys, hope you’re well.

Ok, I am narrowing this problem down bit by bit and I’ve got a horrible feeling that it’s an exhaust manifold leak I have. As the car is a V6 and everything is very tight in there I got to get underneath and search for this potential leak.

A mechanic friend mentioned using a stethascope on the exhaust down pipe and manifold to ”track” the leak. Any idea how to do this i.e. what should I be hearing? Presumably I’ll be looking for the noise to get louder through the sthascope?

The only thing I am concerned about is actually locating a hole, I’ve heard pin hole leaks I won’t see anything and hardly hear anything.

Any help you could give me would be great! 🙂

Cheers.

[Steve Webb]

Hi guys, hope you’re well.

Ok, I am narrowing this problem down bit by bit and I’ve got a horrible feeling that it’s an exhaust manifold leak I have. As the car is a V6 and everything is very tight in there I got to get underneath and search for this potential leak.

A mechanic friend mentioned using a stethascope on the exhaust down pipe and manifold to ”track” the leak. Any idea how to do this i.e. what should I be hearing? Presumably I’ll be looking for the noise to get louder through the sthascope?

The only thing I am concerned about is actually locating a hole, I’ve heard pin hole leaks I won’t see anything and hardly hear anything.

Any help you could give me would be great! 🙂

Cheers.

[Steve Webb]

Thanks for that info Nico. That’s actually something I hadn’t even considered.

I actually have to replace my rear pads this month so I’ll check their moveability and when I replace the pads I’ll polish up the surfaces that make contact and then I can cross that off the list 😉

Thanks for that 😉

[Steve Webb]

Thanks for that info Nico. That’s actually something I hadn’t even considered.

I actually have to replace my rear pads this month so I’ll check their moveability and when I replace the pads I’ll polish up the surfaces that make contact and then I can cross that off the list 😉

Thanks for that 😉

[Steve Webb]

Thanks Eric, much obliged 🙂

[Steve Webb]

Thanks Eric, much obliged 🙂

[Steve Webb]

Thanks Eric, I’ll look out for that.

Does it make any difference that I’ve narrowed down the problem to cold starts? I think what’s happening is it is very poor acceleration at start up and then it gets better as it warms up. What could this be?

[Steve Webb]

Thanks Eric, I’ll look out for that.

Does it make any difference that I’ve narrowed down the problem to cold starts? I think what’s happening is it is very poor acceleration at start up and then it gets better as it warms up. What could this be?

[Steve Webb]

[quote=”spelunkerd” post=41285]I’m still waiting to learn about how to do a professional fuel injection service. One mechanic told me that the job should be done with each injector individually, not as a group while on the car. I guess I was under the presumption that a bad injector would usually give a lean condition for a single cylinder. But, on thinking about it, if the computer detects a lean condition downstream then it would boost fuel to all, resulting in bad mileage and maybe misfires. Eric, where’s that video you did but never posted, on fuel injection cleaning?[/quote]

Would be very handy to see. I’ve got a spare fuel rail that I’ve pulled the injectors out of so if this is something that can be DIY’d I could practise on them first.

Having said that I don’t think it’s that expensive over here (UK) to get the injectors cleaned. Just really wonderig if this should be done as a service type thing.

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