[Noob alert] Can remapping increase MPG?

[markjay]

If a remap took the engine-out NOx beyond say, EU6 limits, then the car is no longer EU6 compliant. Doubtful that that is entirely legal.

I don't know that that's a fact.

I agree that this should be the case, but I don't think it currently is.

And the MOT test only checks that the car meets certain generic requirements, but the car is not tested against its original spec, which could have easily been done if that's what the law said.

In short, I don't think that at current altering the car's original spec - even if it's no longer EU6 compliant - is illegal, as long as the alteration isn't specifically prohibited (e.g. DPF removal), and as long as the car passes its MOT.

To clarify, passing an MOT test isn't in itself proof that no illegal alterations have been made, it's just failing the MOT test that is significant.

 

[Supernoodle]

Situation in the UK is clear Modifying your vehicle’s emissions: the legal, safety and health implications

 

[Bellow]

And the MOT test only checks that the car meets certain generic requirements, but the car is not tested against its original spec, which could have easily been done if that's what the law said.

It would require the whole EU test sequence - clearly not viable.
I suspect the new proposed legislation that prohibits changes to original software will make remaps a thing of the past - if enforced.

 

[Bellow]

Situation in the UK is clear Modifying your vehicle’s emissions: the legal, safety and health implications

Quote:
''Engine re-mapping may also result in non-compliant emissions.''

 

[markjay]

Quote:
''Engine re-mapping may also result in non-compliant emissions.''

I stand corrected:

"Under the Road Vehicles (Construction and Use) Regulations (Regulations 61(7) and 61A(3)) and the Road Traffic Act 1988 (Section 42) it is an offence to use on a road a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards it was designed to meet."

But, again, this means that fitting larger wheels is illegal.........

Unless by 'designed to meet...' the intention was the wider EU6 classification rather than the original specifications of the particular vehicle?

In other words it's not illegal to increase emissions as long as the vehicle doesn't exceed the generic standard it was originally classified under (e.g. EU5 or EU6 etc)?

 

[Bellow]

I stand corrected:

"Under the Road Vehicles (Construction and Use) Regulations (Regulations 61(7) and 61A(3)) and the Road Traffic Act 1988 (Section 42) it is an offence to use on a road a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards it was designed to meet."

But, again, this means that fitting larger wheels is illegal........., perfectly possib

Not necessarily.
My smart started out with 145s on the front and 175s on the rear and ended up (via 175F and 195R) with 195s all round the mpg (and CO2) was the same for all three set-ups. Any loss to aerodynamics and/or inertia was compensated for by increased cornering speed. In a rural setting, entirely possible.
Arguably, the phrasing could be interpreted as either with the new wheels fitted the EU standard could still be met but with increased CO2 (as per a model somewhere in the range) or, the mod is easily reversible so the core of the car can be considered unmodified....

Unless by 'designed to meet...' the intention was the wider EU6 classification rather than the original specifications of the particular vehicle?

In other words it's not illegal to increase emissions as long as the vehicle doesn't exceed the generic standard it was originally classified under (e.g. EU5 or EU6 etc)?

.... whereas changing engine parameters to increase cylinder pressure is a one way ticket to exceeding permitted levels of emissions - esp NOx - that would exceed the EU limits and that no model in the range has those engine parameters (map) as standard.

 

[Pip123]

Right folks, there seems a few knowledgeable folks on this thread so I'm gunna ask..

I have a 15 plate E class 250 CDI coupe ( NONE ADBLUE)

Now my question is, I have remapped my last 5/6 Diesels and have seen decent gains and a nice shove when you press the go pedel, now my Merc has HAD the emissions software update prior to my ownership.

So will a remap effect the NOx sensors in a bad way on these Mercs?

I DON'T intent to map out the EGR or remove the DPF I'm just getting a straight remap with rolling road to fine tune the map to my car..

Having never had a Merc before ( Vag/Audi/Porsche man before) I'm reading so much about these damn NOx sensor issues..

Thanks

 

[suty455]

From someone who has had it done yes it can because its all about the efficiency of the burn ie how many calories per litre does your fuel give, you can approach it 2 ways, the old fashioned no smoke no poke way when we basically turned up the fuel screw on the mech pumps or the modern way which analyses the actual burn on a rolling road and adjusts it, if you get more power out of the same amount of fuel as before its better but am sure someone will disagree.
The flip side is for the first few Weeks you cant help exploring the new found torque and power so you will deffo use more fuel!
I now average 40-44 mpg mixed driving on my E350 previously it was 38-40 so only a few extra miles a gallon but I have way more power if i need it and the overall drive experience is much better, nothing makes you smirk more than blowing off the nerd in his Golf gti in your diesel estate, am finally getting the new exhaust I promised myself this weekend so a new intercooler will swiftly follow and that should see 310-320 bhp and at least 710nm more than enough for normal roads or the standard drivetrain