[guineafowl21]

Hi all

54 plate Td4 manual with about 125k miles.

Economy has dropped from about 500 miles/tank to 400 and is still dropping. Brakes all free and seems to roll fine. No error codes.

Exhaust seems to smell of diesel and is bluish tinged, engine not using oil, CCB filter changed at each oil change (twice yearly).

Takes a few winds to start, lumpy once started, but goes well after that. Definite lumpiness at 2k rpm unloaded.

Pscan at key on/engine off:

Pscan at idle:

Pscan at 2000 rpm:

Also, the injector balance function shows some correction at idle but when revved to 2k the values revert to zero, just as the lumpiness starts.

So, I'm thinking overfuelling, but as you can see the LP pump pressure drops off at higher revs. Can anyone shed any light on this? @pscan.eu ? @Nodge68 ? I'm starting to get a little lost...

 

[Nodge68]

You LP pump pressure is low. It wants to hold at 350Kpa at full power. 340 at 2K uploaded is too low.
Mine does a consistent 29 Mpg. I have a slight misfire if the throttle is held 2K Rpm and smoke held at that Rpm too. I don't get the 2K misfire on the road, unless I'm going down hill on a very light throttle.
I've done loads of checks and found nothing amiss. I've now stopped trying to find a fault that doesn't want to be found.

 

[guineafowl21]

Thanks, Nodge. I know what you mean - our last FL was as you describe but this is a different story. The exhaust stinks and it's down to 200 miles/tank now.

 

[Nodge68]

Have you checked all the boost hoses for leaks? Is the MAP sensor blocked? Is the MAF OK. 200 miles a tank is well down. I think mine goes closer to 400 miles to the tank. Mine is an auto and I don't hang about. I'm getting 28.9 Mpg as of last fill and I've been using my FBH parking heater lots recently.
You definitely need to check everything carefully.

 

[guineafowl21]

Have you checked all the boost hoses for leaks? Is the MAP sensor blocked? Is the MAF OK. 200 miles a tank is well down. I think mine goes closer to 400 miles to the tank. Mine is an auto and I don't hang about. I'm getting 28.9 Mpg as of last fill and I've been using my FBH parking heater lots recently.
You definitely need to check everything carefully.

Boost hoses OK
Map cleaned out but notice above the reading stays at 98 kPa even at 2000 rpm
MAF ? Not sure but looks clean but readings could be out.
No FBH on mine.

I might re-scan and report back.

 

[lenny1234]

Have you filled up at Tescos?

I have auto TD4 and normally I get 420-440 miles per tank. Two fills at Tesco's and I got 380 miles and 360 miles. Filled at usual place and back to over 400, although this cold weather the fuel burning heater likes to fart fumes at me and chew diesel on the short trips

 

[guineafowl21]

Have you filled up at Tescos?

I have auto TD4 and normally I get 420-440 miles per tank. Two fills at Tesco's and I got 380 miles and 360 miles. Filled at usual place and back to over 400, although this cold weather the fuel burning heater likes to fart fumes at me and chew diesel on the short trips

Thanks all. To answer Lenny, I'm a bit cynical about this Tesco fuel business, but I know I can't comment on your individual vehicles, driving styles, locations etc.

I used to do 20,000 miles/year in my Td5 Defender. That's a lot of fill-ups. I always reset the milometer and noted the amount of diesel (kept receipts for tax etc). I did several two-week trials of Tesco diesel, then the same for Esso. I could discern no difference in the mpg or performance. Apart from this, I have owned the vehicle for nearly ten years and almost always fill up at Tesco. Over 60,000 miles and these ten years it has never failed to start or run roughly/smoked.

The Freelander is back up to 500 miles/tank - I swapped over the MAF sensor from a parts car. This, I might add, is also run on Tesco diesel almost exclusively. I guess the MAF was over-reading.

 

[Madmustang]

Boost hoses OK
Map cleaned out but notice above the reading stays at 98 kPa even at 2000 rpm
MAF ? Not sure but looks clean but readings could be out.
No FBH on mine.

I might re-scan and report back.

Also get under the car and check for wet patches. You may have a leak somewhere in the fuel system