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Discussion Starter · #1 ·
Morning helpful elves of the forum,

Right, my 'car' attention has passed to The Black Box ahead of my annual Alps trip.

Engine wise the EGR and CAT have been deleted (and coded accordingly), a panel filter has been installed, it has been serviced (no plug change) and the nice blokes at AMD have remapped it.

I do use Diesel Rhino.

The top of the air box is damaged so doesn't seal properly before the MAF (I have a new one awaiting delivery) and one of the intercoller pipes was damaged and replaced. There was some oil in the pipe but I haven't seen any evidence of it spraying out.

I am assuming that as part of the remap the car was scanned for faults and that none were found. It would be pointless trying to tune a faulty running engine.

My dash read out on the trip computer says I'm getting between high 40s and mid 50s on my journeys since the remap (it was low low to mid 40's before). However, having done a tank of fuel since the remap, Fuelly.com is giving me a figure of 36mpg (the Beast was better than this).

The Beast was only a couple of mpg out (as are the two Seats of a friend) so I am assuming that something is amiss. The engine runs smooth and doesn't smoke.

I was going to start by checking the MAF, the vacumm hoses and the intercooler pipes. Anything else to check?

I'm off to Scotland for the weekend so can do a Fuelly update but some pointers would be appreciated.

Have a good one.
 

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The remap will affect the dash read out. Most maps are written this way as its quick, easy and helps the sales pitch of improving MPG. In reality the ECU is injecting more fuel than it thinks it is.

Any air leaks post MAF will also affect this, but you state the IC pipe has now been replaced. Data logging, general car health check, then the usual tyre pressures etc.
 

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Discussion Starter · #3 ·
Cheers.

I should have made it clear that It was reading way out before the remap too. Post remap both figures have gone up (improved) - the dash figure and Fuelly.com one.

Looks like a poke around the [cramped] engine bay is on the cards. I'll do it when I replace the undertray (it's broken) and the turbo oil feed pipe.
 

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Have you done the sanity check method of manual fuel economy calculation just to be sure that it is not a bad reading by the app ?

Before looking too deeply I would fill and note the amount in liters you filled with.

Run the tank down to the light.

Refill and then work out the economy based on the amount you refilled with in gallons (4.55L per gallon UK) divided by the number of miles traveled.

At least then you can tell for sure.
 

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Discussion Starter · #5 ·
I don't think the app is using bad math. Its a pretty basic calculation. Rough check [in my mind] when entering the data usually gets a similar value. Checked the miles traveled on both the sat-nav and google maps too.
 
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