27mpg average over 10 tanks
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Joined: Mar 2015
Posts: 5
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From: Stockton On Tees
My Ride: 525d M-Sport Auto
27mpg average over 10 tanks
Hi folks,
Hoping someone else has previously had and rectified the economy issues I have.
Bought a 525d auto a few months back, 96,000m, FSH. Really pleased with it but cannot get it to deliver more than 27mpg average... Even on a run.
So far I have done the following, not all fuel related but worthy of note : DPF delete (removed brick and also in software), EGR delete (software), swirl flap delete (software), remap. It was running at 60-70degC so I tested and replaced EGR thermostat (which was indeed stuck open), this got my temps upto around 80... So I changed the main thermostat, which after bench testing, looks to be working reasonably well but not perfect (tested tonight and it opened at 80 and closed at 75(stamped at 88)). The new thermostat has made it worse as it now runs between 75 and 80 and takes a good while to get there.
Any ideas on what else could cause bad fuel economy? I was considering having my injectors tested but I'm reluctant as it runs smoothly; I would have expected lumpyness on tick over.
Many thanks in advance,
Cheers,
Phil
Hoping someone else has previously had and rectified the economy issues I have.
Bought a 525d auto a few months back, 96,000m, FSH. Really pleased with it but cannot get it to deliver more than 27mpg average... Even on a run.
So far I have done the following, not all fuel related but worthy of note : DPF delete (removed brick and also in software), EGR delete (software), swirl flap delete (software), remap. It was running at 60-70degC so I tested and replaced EGR thermostat (which was indeed stuck open), this got my temps upto around 80... So I changed the main thermostat, which after bench testing, looks to be working reasonably well but not perfect (tested tonight and it opened at 80 and closed at 75(stamped at 88)). The new thermostat has made it worse as it now runs between 75 and 80 and takes a good while to get there.
Any ideas on what else could cause bad fuel economy? I was considering having my injectors tested but I'm reluctant as it runs smoothly; I would have expected lumpyness on tick over.
Many thanks in advance,
Cheers,
Phil
New Members
Joined: Mar 2014
Posts: 55
Likes: 0
From: UK
My Ride: 530D Touring
Look into the transmission oil cooler.
It runs the gearbox oil through a heat exchanger with the engine coolant and they have a thermostat that can stick open and saps heat from the engine.
I don't know anymore than that but read about it before I changed my stats and got temps up to 88. From 65.
My 530d will do 42mpg on a run at 70mph. Yours should do more
It runs the gearbox oil through a heat exchanger with the engine coolant and they have a thermostat that can stick open and saps heat from the engine.
I don't know anymore than that but read about it before I changed my stats and got temps up to 88. From 65.
My 530d will do 42mpg on a run at 70mph. Yours should do more
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