16 replies to this topic

[Boabymiller]

Advice needed - I have a 2014 335d xdrive which I want to give a bit more BHP to. The car is still under warranty and cannot be remapped by simply plugging in a laptop. The two options I have are to fit a tuning box - the one supplied by tdi tuning looks a decent option or I send it to a local remap specialist (ecotune) where they will open up the Ecu and properly map the ecu. Both are roughly the same price and just looking for a bit of advice on pros and cons as both suppliers understandably say their option is best 🙈

[siztenboots]

if you cannot reprogram it over the OBD port , then it is necessary to split the seal on the ECU to get access to the circuit board. Then a special cradle is placed over to allow some probes to attach to very small contacts, then this cable is attached to the laptop and bench flashed with a custom calibration. a tuning box will attach itself in between the engine loom on varies sensors, and will send back a false signal to the ecu to fool it and may improve torque in some areas, or worse.

[fezzasus]

I just wouldn't

 

Out of the two, I'd go for a proper map, but I'd want it mapped without causing excessive engine out smoke.

 

You'll likely kill the injectors, clog the DPF and have significant piston deposits with whichever option you go for.

[slindborg]

I just wouldn't

 

Out of the two, I'd go for a proper map, but I'd want it mapped without causing excessive engine out smoke.

 

You'll likely kill the injectors, clog the DPF and have significant piston deposits with whichever option you go for.

 

You there, with your sense and reasoning....

 

What he said. If you MUST, then have it mapped (recalibrated) as opposed to chooning boxed to ruin things

[PaulCP]

Chip tuning boxes gain the extra power through over fuelling the engine. It works, but at the end of the day it's your engine, and some are more sophisticated than others in what they measure and what safeguards are built in. Many claim to be digital but contain no more than a simple resister. The less sophisticated ones can also cause more "diesel knock" when the engine is cold Below is an extract from a publication summarising how they work. All of the limitations are overcome by a correctly calibrated remap since this will take into account adjustments to many other engine parameters monitored by the ECU. Diesels aren't too fussy about Air/Fuel ratios, they will often continue to make power when incredibly rich, and producing huge clouds of black smoke. Take a look on Youtube at some of the big power Diesel Drag cars and trucks. In OEM Diesel tuning for the road, the limitations are usually based on the amount of smoke produced, and the amount of power the chassis can handle. Big BHP figures on a diesel are easy to make, and choosing the Tuner with the highest figure can sometimes be just picking the bravest. It's easy to be brave with someone else's engine. Intercepting the Rail Pressure sensor is the key to Tuning Boxes. The ECU/engine will control the pressure, and it uses its sensor to confirm this. This figure is vital for the ECU to known the fuel quantity. Adding a resistor into this sensor circuit passes the wrong information to the ECU. What was 1500bar is now reported as 1400bar, so the ECU will activate the high pressure injection pump to raise the pressure by 100bar above the sensor value. The extra pressure will force more diesel through the open injector, and as mentioned, for a diesel, more fuel = more power. There is safety factors and tolerances built in, but in all cases, the Injector pump is now doing more work providing the extra pressure, and the Injectors are now holding back greater forces. The Torque and Smoke limiters have been bypassed as the ECU doesn't realise the greater fuel flow, and more interestingly, the MPG is screwed! Economy and Tuning Boxes From the original calculations in the ECU, and the Vehicle Road Speed, the ECU will be able to calculate the quantity of fuel used per unit of distance traveled. But what happens if the quantity of diesel injected is higher than the value the ECU is expecting? In this case, the economy will be overestimated as the ECU thinks it is using less diesel than reality. As with most external changes, if one calibrated component is disturbed, the knock on effects will be far reaching. That's not to say that there isn't an increase in economy, there will be changes, and often the economy does increase, but certainly not to the level that the On Board Computer or Trip Computer thinks.

[Boabymiller]

Hmmm, it's a tough one. Just not convinced physically opening the Ecu etc is the best idea as the advice is to take it back and have it put back to normal every time the car going into the garage where as could just unplug the box. If it could have been done through the obd port it would have been a no brainer 😬

[jimn]

I fix BMW's for a living and i get a lot of customers asking if i can remap there cars for them but its something i have looked at then disregarded. Primarily because BMW like to make it very difficult to do and secondly because its a bit of con..

 

I know a little bit about tuning petrol turbo engines as i did my own evo when i had one and mapped my brother in laws punot gt when it was running on megasquirt and i know first hand how much time, distance and fuel it takes to get it right.

Knowing this i have a bit of a problem with have a go heroes charging alot of money for diesel 'remaps' as they are just generic "bought off the shelf" maps that turn the boost up and throw more fuel in. I get that you can tune a diesel much more crudely than you can a petrol but there is very little if anything 'custom' about the remaps most people sell for a diesel engine. Its just the new more convenient way of superchiping a car which most people these days turn their noses up at..

 

Having said that.. I did 'remap' my own 320d daily driver using an mpps lead and software i bought off ebay and sent the file to someone i found on the internet as a bit of an experiment.

 

The outcome seemed to be as much boost as the turbo could make (even at idle as you can here it whistling its bollocks off from cold) and sh*t loads of black smoke when you floor it from low revs.

 

It is quicker but it definitely uses more fuel.

 

The other thing to bare in mind is when you plug a car into ista (BMW diagnostic software) and the ecu has been flashed by a third party you get a warning saying something has been tampered with and that no components of the car will be covered by bmw warranty or goodwill.

Obviously if you have a problem with another area of the car other than the engine and they dont plug it in you will get away with it but engine issues, especially difficult faults would be kicked back in an instant.

 

I say the tuning box is the safest and possibly only way to conserve your warranty but be prepared for potential DPF issues, higher fuel consumption and i guess a bit more mechanical ware on most engine components which if your keeping the car is something to bare in mind.

[The Batman]

Put a bluefin on it, easy to do/remove I got it in my 330d

[KurtVerbose]

Change it for a 550D.

[2GOOD]

Do BMW do a power kit for the 335d? I know they do for 330d.

[2GOOD]

Change it for a 550D.

Not brought into the UK, but nice idea

[KurtVerbose]

 

Change it for a 550D.

Not brought into the UK, but nice idea

 

 

Oh yes, I'd forgotton.

[Code Monkey]

I have a winter shed Fiat Doblo 1.9 JTD, which is a rattly old lump with 100k miles on the clock.

Possibly worth about the last tank of diesel I put in it.

Think it is the only type car were it is sensible to consider the cheap tuning boxes on, anything else the worries about repair costs offset the advantages

This will just be thrown away when/if it breaks down, I haven't tried a tuning box, is interesting looking on eBay the price variation for what looks like the same kit.

[turbo boy]

I agree with the Batman. Blue fin re maps are excellent. I run their stage 2 software on my Mondeo 2.2tdci ST and it made a considerable difference. Their service is excellent too. It's tried and tested. I would rather have cholonic irrigation in Skegness rather than have a tuning box. If you are foing to do it do it properly 👍 Jon

[JG]

get an x40i, any will do.  The engine just seems to be an endless source of power. in the 1 series its very very quick. 

[Dan r]

I'd love to see the results of one of these chipped fully instrumented diesels run an emissions cycle, may put people off a bit and make it illegal! You just know they have no idea what the turbo speed and cylinder pressures are when 'mappin'

[KurtVerbose]

My ancient TD6 Range Rover has a tuning box, came with the car when I bought it. I didn't remove it as I'm not sure how much difference it makes - it's quoted a mighty 14bhp more. Anyway, the car's done 145k miles now with only the odd replaced injector and glow plugs, and that's with a fair amount of towing a 3500kg trailer.

 

Not recommending a tuning box, and I wouldn't fit one, that's just been my experience. Doubtless there are others with more sorry tales.