The operation of a TDI

[prj]

I made a writeup of the process of chiptuning my Opel Omega, which is managed by the MSA-11 control unit.

The same control unit is used on AAT and AEL engine codes and all newer Bosch control units are based on it.

It contains a lot of information to understand how a diesel ECU works, and if you are remotely interested in such stuff, it should be a good read.

The link is here:

http://prj-tuning.com/?p=163

[Rocco]

Crazy stuff,well done DD,and thanks for share it. Now follow with our old motronic

[prj]

Now follow with our old motronic

All in due time.

[dgacampbell]

Interesting reading!!

[Error404]

A really interesting read, thanks for sharing

[DJones]

Very good, well done..

[4WheelDrifter]

Nice write-up on the old-skool diesel tuning, Dimitri. Thanks for sharing. I especially like the note at the end.
Now get to work on EDC 15 P.

[mcandmar]

Fascinating stuff Dmitri. So in a diesel engine is a majority of the work focusing around injection quantity, as governed by the smoke limiter map, rather than the actual timing of when fuel is delivered? And if so why, is the timing a constant regardless of the amount of fuel delivered?

Also would be interested to hear your opinion on these piggy back TDi tuning box's, how do they work?

[prj]

Nice write-up on the old-skool diesel tuning, Dimitri. Thanks for sharing. I especially like the note at the end.
Now get to work on EDC 15 P.

What makes you think I can't do that already?

Fascinating stuff Dmitri. So in a diesel engine is a majority of the work focusing around injection quantity, as governed by the smoke limiter map, rather than the actual timing of when fuel is delivered? And if so why, is the timing a constant regardless of the amount of fuel delivered?

Timing is not static, and tuning timing in a diesel is a fairly complex concept.
You can read here, if you want:

http://killerbeeperformance.com/download/tuning/Timing%20the%20Diesel.pdf

I did not need to adjust timing, because I did not go outside the envelope to which timing was mapped at the factory, this is explained in the paragraph before the conclusion as well.

Also would be interested to hear your opinion on these piggy back TDi tuning box's, how do they work?

Forget that crap. Just don't do it.

[mcandmar]

Timing is not static, and tuning timing in a diesel is a fairly complex concept.
You can read here, if you want:

http://killerbeeperformance.com/download/tuning/Timing%20the%20Diesel.pdf

I did not need to adjust timing, because I did not go outside the envelope to which timing was mapped at the factory, this is explained in the paragraph before the conclusion as well.

Very interesting stuff, the concept of negative torque is a little scary when you think about it. When my TDi Skoda starts to lose power after multiple hard runs and heat soak im going to be a little freaked out now i have a better understanding of whats actually going on

I would'nt dream of using those super duper power tuning box thingys, but am i right in saying they just dump in more fuel and basically override all the over fueling safety nets the ECU has in place?

[prj]

Very interesting stuff, the concept of negative torque is a little scary when you think about it. When my TDi Skoda starts to lose power after multiple hard runs and heat soak im going to be a little freaked out now i have a better understanding of whats actually going on

Well, don't worry about it, the ECU has correction maps for all that stuff. But if they are tampered with incorrectly by some "italian tuning" (all maps up), then engine damage can result.

I would'nt dream of using those super duper power tuning box thingys, but am i right in saying they just dump in more fuel and basically override all the over fueling safety nets the ECU has in place?

Yes and no. Basically there are different ones. The most funny ones are those that have simply a resistor to trick the ECU in believing the engine is always cold.
Other ones intercept the signal from the ECU to the pump, and just add an amount all the time (that is the same as upping the quantity adjuster map) etc.

Either way, those things are not safe to use, and there is no point either.
ECU remaps are ubiquitous these days, and if it is done properly, it will give more power and better fuel economy, while retaining safety when compared to a tuning box.

However, the tune is only as good as the person making it. You can easily do more harm than good with a bad tune.
When you know all parameters of the ECU, you can do lots of stupid things. Imagine an inverted "Driver's wish" map for example

[prj]

As for my Omega - before, I used to just hold the pedal down almost every time I wanted to accelerate to about 40 kph, then I let off slightly.
Now it is way better off the line, and I rarely use WOT to get from 30 kph to 60kph anymore.
I mean, it's obviously no RS4, but it is a lot better to drive, and the car does not feel like it lacks power anymore for it's weight. Only at start when taking off due to the slight turbo hole.

[rj scotty]

A really good read that laid down in easy to understand terms

Your content just gets better my friend

Can you do the same for the map in my t4 transporter?

cheers

rich

[prj]

Yea, I probably can
Need to read the chip(s) and look inside though.

[andy10v]

Thanks, that was a very interesting read.