alexjc4

My approach is that on one hand the supplier is experienced and knowledgable about EMSs in general and VEMS specifically, and has developed a PnP solution for the 964 over a number of years, on the other hand every car is different and my car, though fairly standard now, may develop in any of a number of directions. So, I need to understand every element of the system and how it will be implemented to work with the std car. This means I'm dependant on the kindness of strangers, forum members, the VEMS diy community and the supplier to share their knowledge and answer my stupid question... so far so good

robt964

Update: the central informer doesn't control the 'check engine' light on the dash. This is controlled directly from pin 22 of the Motronic.

alexjc4

Ooh I haven't looked at the fault reporting on VEMS but it would be cool to drive the check engine from the knock control unit wouldn't it.

robt964

The heater/blower is a signal from the HVAC to the Motronic. The Motronic would normally stop fueling when the engine is overrunning/coasting. When you have the heat on, this signals the Motronic not to do so. - short story, you don't need it.

alexjc4

So what's the idea behind that, to keep alternator perky for the electric fans or ....

robt964

If you're coasting for long periods (down a mountain) you'll very quickly run out of hot air through the vents if the engine isn't fueling as the heat exchangers will start to cool off. Not a problem we'll encounter in blighty

alexjc4

Lol yeah that sounds vital! Especially since my HVAC seems to have trouble maintaining a stable temp within about 20degC at the best of time.

Ducks964

Great thread. I will follow and let you know how it goes with my VEMS system and how well it handles the TPC supercharger.

Raceboy

Hi Michael and Alex,

VEMS has warning light feature that you can use in many easily configurable conditions but also as a shift-light if desired, though it would be better to use something more visible for that.

ghhally

Currently doing the same based on KMS MD35

alexjc4

That's a nice looking ECU, will you be making your own 55pin harness adapter?

http://kms.vankronenburg.nl/products/ecus/md35/

alexjc4

Thanks Peep, that looks nicely configurable.

For those that haven't caught on, Peep is supplying Michael and me with the specially adapted PnP VEMS system, and has been very helpful and forthcoming with information. Peep has been working with VEMS for ~8 years.

robt964

>Peep is supplying Michael and me with the specially adapted PnP VEMS system

Can you elaborate on what changes are being made to the regular 55pin VEMs to make it suitable for this application?

alexjc4

The plug is the same but the pin out is different as I understand it, the vems.hu PnP is offered in Audi and BMW specific versions mainly I believe, though I guess they would configure it how you wanted it you knew every last detail and could provide them in a way they understood. Compared to the Audi/BMW versions obviously the injectors, ignition, triggers and sensors will all be slightly different. So partly wiring differences, partly configuration, and of course calibration of a decent base map. The 964 PnP is built from components rather than an adapted off the shelf PnP version. Peep may have more input, but to fair it's his "secret sauce" - to share or not as he wishes.

Given enough time, I think I could lash something together (I'm sure you could) using a standard VEMS v3.3 and build my own adapter (you can buy DIY 55pin break out boxes on ebay), but life's too short

robt964

>but life's too short

Absolutely, if the problem is already solved and offered at an acceptable price it makes total sense.

How will the base map be derived? Have you supplied ignition, fuel, temp, dwell maps from the Motronic?
Given its wideband capability, do you plan on developing the base map yourself?

Sorry - I have lots of questions