Car fuel additives - Do you use one?

[SueEllen]

It's the oxygen free ones with gold ends you want to get

[Eirikur]

Supermarket fuel comes from exactly the same refineries as "branded" fuel.
I've seen the same lorry stop at Tesco to unload fuel and it then went on to the Esso petrol station next door but 5p/l more expensive

[GigiBronz]

Good question!
(1) Putting aside the legal issues, I would love to remove the ERG and DPF etc. However, remapping can f**k up the ECU if it's not done correctly and that would end up costing £1000 + to put right. Anything can go wrong when remapping so the car electrics have to be in perfect condition with a power back-up while doing the re-mapping.

(2) The depollution system is partly designed to get rid of nitrous oxide but by doing so it lowers the combustion temperature by pumping exhaust into the inlet. The result is a small amount of black smoke of which is removed by the DPF. Do away with the EGR system and your engine will run better and use less fuel but it's illegal.

(3) By trying to fix a problem by doing a delete EGR is merely coving up the symptoms but the original problem will still exist and come back to haunt you in a different form. You need to find the underlying problem. You need a good garage to diagnose the issue but there are very few good garages. There are a few self-employed specialists who will come to you or a garage to diagnose the car.

(4) Back to basics. A Diesel engine needs air, fuel and most importantly high compression. The most common failure causing black smoke is the lack of compression. Solve the issue and the DPF will take care of itself. The DPF and EGR issues are symptoms not the causes.

I've been watching most of your post, they are quite accurate. I presume you've done work in the sector?

(1) Putting aside the legal issues, I would love to remove the ERG and DPF etc. However, remapping can f**k up the ECU if it's not done correctly and that would end up costing £1000 + to put right. Anything can go wrong when remapping so the car electrics have to be in perfect condition with a power back-up while doing the re-mapping.

most of them only cut the egr and increase the smoke limit( or max amount of fuel allowed for a mass flow of air). But they do not have all the measurement equipment in place and only rely on sensors on the exhaust to sense if they are closer to some hardware limit. it is generally thought that you might have some safety margin in an engine ... in the manufacturer calibration but in practice it might not be quite so - you don't know what components your engine was made with and where it lies in terms of air and fuel delivery in the population distribution.
production calibration is made ideally for nominal engine and compoents

those things are quite hard to do on a dyno, if you do them on the road...
you might find some tested calibrations online but I am not sure how well tested they are.

but on the other hand, not all components that you have on the vehicle are 'nominal' which means that they might behave differently then initially expected. also injectors, turbocharger, EGR might age and you will have deviations in setpoints and calibrations going all over the place.

if you deactivate the EGR, it depends on how that engine was initially calculated but if the turbocharger was picked with an 'EGR open at all times' that will deviate some of the energy in the exhaust gases, you will find that your turbocharger might exceed critical speeds (or not find out until it prematurely fails).

there is less development effort nowadays in making engines, also they are made to last a specific number of hours because they've discovered how to build them better to requirements. they do not have to over-engineer.
best would be to not alter any of the calibrations.

[Lance]

It's the oxygen free ones with gold ends you want to get

nope. They're the £50 ones.
You need cryogenically treated cables.

[Uncle Albert]

Cryogenically treated cables are fine for a hobbyist. I have mine specially contructed from stem cells extraced from Iranian albino Beluga eggs.

[DoctorStrangelove]

There is a government team with the police, DVLA, VOSA and local and local authorities who have set up roadside checks. They will plug into you ODB2 port and check. If mods to the depollution system are found, your vehicle will be impounded.

I wish them luck with a Rover 90 P4.

[DoctorStrangelove]

Those the gods wish to destroy they first make mad:

https://www.futureshop.co.uk/nordost...iABEgJOXvD_BwE



It really does say £17070.00.




The septic lunatic version of some 10 years ago was a bargain at $2000.

[Lost It]

Right up to the point you make a claim and they find out you've modded the vehicle and not told them about it But yeah, definitely worth the risk

Yes because the insurance companies take every engine apart to make sure it's been modded don't they. Oh. They don't?

[Lost It]

The absolutely best way to keep your derv engined car away from blocked DPF's etc. is to completely ignore the idiotic 10,000 mile oil service claims that the idiot sales people have foisted on them.

For example...

I have a 2005 Jaguar X Type 2.2 derv with 220,000 miles on the clock. It gets oil and filter change every 5000 miles and to date has never needed an injector, never had a blocked EGR (can't be blanked on the 2.2 engine, throws a warning light up) the inlet manifold is still clean and still runs as sweet as a niut. Oh. Never ever has supermarket junk fuel put in it either.

I have a Peugeot Expert van on 260,000, just had to scrap it for corrosion reasons, but again, ran sweet as a nut, same treatment, fresh oil every 5,000 miles. No supermarket fuel.

Supermarket fuel. Right. All fuel has to meet the appropriate British Standard, and it's what the refineries put out whether it's going to tesco or Shell or BP or Esso.

The difference is. the fuel is stored on top of water in the tanks. The Supermarkets are supplied mostly by the "dregs" of the tanks, always the last tankers to fill, before they go to the area where the additive packages are installed which the Supermarkets don't bother with, what you get is base fuel that may or may not have a bit more water in it than normal. And that's why in most cases you will have a slightly lower MPG result with supermarket fuel, because to make the same power you kind of need more right foot.

You may well be one of these people that will swear that they have never put anything in their car but supermarket junk, and never had a problem. But I'd suggest there are more real life unicorns... The manufacturers build engines that will last the warranty period is what used to be the case, but modern machining is far better than that and it's quite common to get 200,000 plus miles from derv engines these days. If you treat them right, use decent fuel with a half decent additive package, the occasional "Italian Tune up" and it will see you right.

IMO of course.

My best one by far, I had an old Series 5 BMW 2.5TDS that I managed to get to almost 600,000 miles on a selection of cooking oil, ESSO fuel and the occasional shot of Redex before the front suspension mounts turned to dust... And unless I'm very much mistaken the guy who bought the engine for his Range Rover is still getting good service from it. Again it had 5000 mile oil changes when I had it...

Motorbike wise I had a 1992 VFR 750 with 170,000 miles on the clock before I sold it. Again, regular oil changes were all I really did to that jewel of an engine...

You see I buy my cars to run until they expire, either through rot or not being able to get parts. Not really one for new stuff, in fact my newest car is a 2007 Lexus RX400h... 180,000 miles and still going strong. Again 5000 mile oil changes...

Truth is the motors these days are so micro managed with knock sensors that will retard the ignition to stop it punching holes in pistons, built in rev limiters to stop you centrifuging all the oil out of the crankpins, variable valve timing so it never really runs fuel rich etc. that you rarely get to a stage where the driver can actually damage them. Unless that driver thinks the 10,000 mile service interval means the oil doesn't have to be checked at all of course.

Except the DPF systems that add more derv to the fuel to raise the combustion temp in an effort to make the DPF "fire up" and burn all the ash out... These are the dodgy ones because if you get too much derv in the oil it will eventually be so over full and thin that the engine will start consuming the sump oil and nothing short of blocking the air intake will stop that from running to destruction. It will stop when it runs out of sump oil.... And who wants to approach a Derv engine trying to get to valve bounce to take an inlet pipe off and shove a rag in there? Not me...

But it's your money, if you think you can make a case for putting not so cheap these days supermarket fuel and the odd £5 tin of additive in to "clean it out" then go for it.

[Paddy]

The absolutely best way to keep your derv engined car away from blocked DPF's etc. is to completely ignore the idiotic 10,000 mile oil service claims that the idiot sales people have foisted on them.

For example...
bla, bla bla

Frequent oil changes are good but the remainder is a load of unscientific bolox