Too juicy??

[Laird Scooby]

Originally Posted by deeman940

I suspect what he really means is on the dual carriageways/motorways he was driving, for the most part, at about 80mph which isn't 80mph average speed.


That's what i meant Dave, thanks for clarifying, right so it does appear to be guzzling!
The car has been de catted so that is not an issue!!
Could it be a clogged AMM? (suspected) or a dirty throttle body? (suspected)
The Lambda/ emissions light came on on the first trip to Plymouth, is this a clue?

Are you able to read the codes? If so, that's the first thing to do and i'd strongly suspect (due to the lack of cat) that the CTS has gone for a can of worms.

If it's generally driving ok with a rough idle and a bit of hesitancy, not great starting then that would also point towards the CTS if it's drinking like Oliver Reed on the rampage!

To a certain extent the Lambda sensor will enable the ECU to "tune out" the excess fuel but there will likely come a time when it can't and the adjustments that it's telling the system to make aren't happening so it throws a fault code.
It could even be the Lambda sensor itself especially if cold starting isn't effected (normally floods on a cold start if the CTS is dead) so reading the codes will save you a lot of time and money.

If you can't read the codes but can drive a multimeter, we can still test things the "old fashioned" way.

[deeman940]

Originally Posted by Laird Scooby

Are you able to read the codes? If so, that's the first thing to do and i'd strongly suspect (due to the lack of cat) that the CTS has gone for a can of worms.

If it's generally driving ok with a rough idle and a bit of hesitancy, not great starting then that would also point towards the CTS if it's drinking like Oliver Reed on the rampage!

To a certain extent the Lambda sensor will enable the ECU to "tune out" the excess fuel but there will likely come a time when it can't and the adjustments that it's telling the system to make aren't happening so it throws a fault code.
It could even be the Lambda sensor itself especially if cold starting isn't effected (normally floods on a cold start if the CTS is dead) so reading the codes will save you a lot of time and money.

If you can't read the codes but can drive a multimeter, we can still test things the "old fashioned" way.

Sorry for my ignorance Dave, what's a CTS??
car starts fine on cold start

[360beast]

Originally Posted by deeman940

Sorry for my ignorance Dave, what's a CTS??
car starts fine on cold start

ECU coolant temp sensor, tells the ECU the temperature of the coolant to richen the mixture up during cold start/running.

[360beast]

Originally Posted by Laird Scooby

That's about 34mpg Luke, not bad at all.

Is that for normal unleaded Luke? It was 124p/L for Super until recently and jumped about 10p/L in a fortnight!

Yeah normal 95 unleaded, the expensive stuff I haven't looked at but I know it is over £1.30 a litre.

A couple months ago it was £1.17 a litre and then overnight it jumped up and hasn't budged since.

[Laird Scooby]

Originally Posted by deeman940

Sorry for my ignorance Dave, what's a CTS??
car starts fine on cold start

Exactly what Luke said :

Originally Posted by 360beast

ECU coolant temp sensor, tells the ECU the temperature of the coolant to richen the mixture up during cold start/running.

If it's fine on a cold start then it could be the CTS still (if it's only halfway dead) or possibly the Lambda sensor but the only way to know is either read the codes or do some tests.

Originally Posted by 360beast

Yeah normal 95 unleaded, the expensive stuff I haven't looked at but I know it is over £1.30 a litre.

A couple months ago it was £1.17 a litre and then overnight it jumped up and hasn't budged since.

That would be when super unleaded was 124p/L as well then and when it jumped up it went to 134/L round here.

Still cheaper than V-Power at 150+p/L and both my beasts perform and go further on Sainsburys/BP. That said, i'm not sure BP still supply Sainsburys as they no longer have Nectar points on BP.

[TonyS9]

Originally Posted by Laird Scooby

£5/gallon????? I want the address of your filling station! Round here it's about 135p/L which is about £6.60/gallon

On a rough approximation,...

As you say it was a rough approximation for ease of calculation. Also your estimate of 10mpg validates my calculation of single figure mpg.

Anyway going by cold engine running. It typically starts over 1g/hr then drops to 0.3g/hr when warmed up, in the winter, so cold read from the sensor could easly do it. I would start there.

[Dirty Rooster]

Originally Posted by deeman940

... so it does appear to be guzzling!
The car has been de catted so that is not an issue!!
Could it be a clogged AMM? (suspected) or a dirty throttle body? (suspected)
The Lambda/ emissions light came on on the first trip to Plymouth, is this a clue?

In my experience a dirty throttle-body doesn't affect normal driving MPG, mostly messes up idle consumption. (I'm OK with being wrong on this point)

I would look at the O2 Lambda sensor, but only after doublechecking tyre pressures and brake caliper sliders.

When my odometer was working I was getting 30 & 31 mpg (2.0 turbo 940) and slightly more on Shellvpower(whateverr it's called this week).

[deeman940]

O.k chaps, it has been a while and my problems are still persisting, since last posting i have replaced the Lambda sensor ( gen BOSCH) which has got rid of the light after a reset and cleaned the AMM and replaced the RAMAIR filter with a standard paper one.
I still have pretty bad consumption, a constant smell of petrol..not too heavy but it is there, fairly regular backfiring on the overrun and in the last few days have been experiencing fuel cut under heavy load in 1st and 2nd gear, Why is the car running so rich??
I thought i might of been experiencing boost creep from my MBC which was already fitted to the car when i got it so turned that down a notch so is boosting at 0.5 bar but still had fuel cut earlier....
Another problem i have is that after a bit of slightly spirited driving i seem to have a high idle (1500 rpm) which goes away if i switch the ignition off then on again.
Are the two problems related? Could it be a faulty AMM? or idle control valve? or both? or even the CTS still as suggested before?
Any help would be greatly appreciated as the consumption is starting to annoy me slightly!! i wouldn't mind if i was getting performance to match!
Tyre pressures are fine and no sticky caliper issues...

[Laird Scooby]

Originally Posted by deeman940

O.k chaps, it has been a while and my problems are still persisting, since last posting i have replaced the Lambda sensor ( gen BOSCH) which has got rid of the light after a reset and cleaned the AMM and replaced the RAMAIR filter with a standard paper one.
I still have pretty bad consumption, a constant smell of petrol..not too heavy but it is there, fairly regular backfiring on the overrun and in the last few days have been experiencing fuel cut under heavy load in 1st and 2nd gear, Why is the car running so rich??
I thought i might of been experiencing boost creep from my MBC which was already fitted to the car when i got it so turned that down a notch so is boosting at 0.5 bar but still had fuel cut earlier....
Another problem i have is that after a bit of slightly spirited driving i seem to have a high idle (1500 rpm) which goes away if i switch the ignition off then on again.
Are the two problems related? Could it be a faulty AMM? or idle control valve? or both? or even the CTS still as suggested before?
Any help would be greatly appreciated as the consumption is starting to annoy me slightly!! i wouldn't mind if i was getting performance to match!
Tyre pressures are fine and no sticky caliper issues...

What are you like with a multimeter? If it's still as bad as it was and the other symptoms are pointing to it running rich, prime (but not the only) suspect is the CTS so worth measuring the resistance on it. Colde should be about 2500 Ohms from each terminal to earth/cylinder head and about 5000 Ohms between the two terminals (sum of the two resistances) when cold.

If it's higher, chances are it's the CTS has gone for a ball of chalk.

Also worth checking your FPR - Fuel Pressure Regulator - is faulty. With the engine running, pull the small bore tube off the FPR and plug those tube/hose with your thumb to repvent an air leak into the inlet manifold and all that can cause.
Observe the engine note as you do all this and also the small stub on the FPR - if fuel leaks out of it, the FPR is FUBAR and needs renewing.

Rock Auto in the USA is a lot better on price than anything local!

See what you can find out on those two tests and we'll go from there.

[aardvarkash10]

@80mph regardless of where, you should EXPECT significant fuel use.

You are pushing a 1.7 tonne housebrick through 2.1m2 of air resistance and dragging a similar-sized vacuum behind you. That all comes at a cost.