MPG ? COLD WEATHER & SHORT RUNS?

HERBIEMERCMAN

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Hello Everyone, Some weeks back my MPG had noticeably dropped i am used to 25MPG on short local runs and 34MPG on long runs, M/Way etc. I have a e-300 td Elegance estate, owned it from new in 1997. Anyway i decided to have the injectors replaced or reconned which ever my Inde decided, it was the latter, recon he chose.

Post the operation i spent a week on short runs and cold weather, lots of stop starts etc, paradoxically instead of an improvement in my MPG i got 20MPG? I measure my MPG, tank to tank so the results are accurate, i am not "crying wolf " yet, and i am seeing what the next couple of weeks brings? The car runs beautifully, smooth and lively etc, all be it i am not one for putting my foot down, i drive sedately sedately on local runs.

My Inde is a top class guy and there is nothing to check at his end, the recon processors are where any faults could be, and it was carried out by a major diesel engineering company, "Merlin Diesels".

I am not familiar with the details of the actual process, if the flow patterns were within their limits, then i suppose they could do nothing to one or more of the injectors, i know the injectors have springs and seals but what the potential is for them "messing up" i do not know? My previouse experience with "Merlin Diesels" was 9 years back and some 100,000 miles on the same OEM injectors, the recon was ok but they did not tighten the boost pipe retaining bolt and over several weeks i gradually lost boost all together, cost me money, time and frustration.

So where do i go from here if the poor MPG continues? I cannot see "Merlin Diesels" letting me or my Inde stand and watch them test my injectors? just may be they might trust our situation and provide us with some new injectors FOC? Do any other members have any advice, which will be appreciated? Herbie.
 

umblecumbuz

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You are in the unique position of having records of your car's long history, as its only owner.
Although Merlin Diesel seems to have a good reputation, anyone - even them - can produce an 'off job'.

Why not contact them, through your Indie if appropriate, and give them your fuel consumption records both before and after their work, asking them for reasons why their refurbishment has produced such poor and disappointing results?
After all, it must have been in the interests of better fuel consumption that was one of your reasons for using them.
 

malcolm210

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If the mpg doesn’t improve as the weather warms up or you feel that that isn’t the problem I would lift one of the injectors and have it flow tested by a third party to check the tolerances. My E350 needed a new thermostat as it was stuck open and this caused a dramatic reduction in mpg similar to what you are experiencing as the engine was on choke most the time. Does sound like the injectors are out of tolerance
 

alexanderfoti

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Keep in mind, the indy may have lost a bit of fuel replacing the injectors and test running the car etc, so this may have skewed your results a bit.
 
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HERBIEMERCMAN

HERBIEMERCMAN

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Hi Gentlemen, Tahank you for your replies, i filled the tank prior to the MPG testing but Alex would be correct in his point, the other major thing i need to point out is that when i discussed the job with my Inde prior to him starting he mentioned "Merlin Diesels", i therefore assumed that they would be doing the restoration job, post the job when i told my Inde that the results were so poor he said that the restoration was done by a smaller company who he had 100% confidence in, never in the past 5 years had he had any problems. He said Merlin were too interested in selling parts, got too big and he did not have confidence in their in house restoration. As i said in my opening thread, re Merlins, they left my boost pipe loose 9 years ago.
However i am soldiering on and being more objective with some longer runs etc, may be i did underestimate the amount of short runs i did in very cold conditions? time will tell.
My Inde is very good and if there is a need to take the injectors for a third party check he will do it, thanks for the idea malcolm,you can't be ("The Great Malcolm") he was a good friend of mine and i never had the pleasure of meeting him. Herbie.
 

malcolm210

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The sort of temperatures we’ve been experiencing over the last few months are bound to impact fuel consumption especially as in my case the thermostat had stuck open I eventually stopped using the car for a couple of weeks until the stat was fitted

As regards Malcolm (TV) I miss his presence, contribution and help on the forum like many on here, sad times but as they say life goes on
 

Frontstep

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Too much fuel usually shows out of the exhaust how is your smoke ?
 

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