Update, I finished the harness tonight

I started with a new ECU connector that I bought from the VEMS guys for around $50 US shipped from Europe:

<a href="http://shop.vems.hu/catalog/product_info.php?cPath=1_5&products_id=109"><img src="http://shop.vems.hu/catalog/images/JPT_55pin_connector_0005_s.jpg" border="0"></a>

Then I sat down with the wiring diagrams to figure out how to remap the pins from motronic to 034. I wont put those up yet because I want to make sure I've got them right obviously.. I left my ECU at the shop with my v8tt coupe project car so any testing will have to wait until I'm back over that way, but the harness assembly is complete.

here's the connector modified so the pins come straight out the back for easier soldering:

<img src="http://www.theswansonfamily.us/modules/gallery2/d/36789-1/IMG_1407.JPG">

And the 'finished' product:

<img src="http://www.theswansonfamily.us/modules/gallery2/d/36793-1/IMG_1408.JPG">

The extra wire going off the screen is a supplemental ground strap just for safety sake since almost everything is sunk to ground through the ECU. The big heat shrink sections aren't shrunk yet because I want to check a few values with the harness connected to the car before securing everything down. All in all I'm happy with the progress thus far. The next step after verifying signals from the car will be to pour non-conductive epoxy onto the back of the motronic connector to prevent the pins from moving around/breaking. I accidentally broke two of the pins that thankfully were unused while soldering the wires to the connector, so I think it needs all the strain releif it can get.

More soon.

Other than this harness, you will need:

A modified crank pulley with 60-2 trigger wheel and sensor bracket:

- <a href="http://www.034motorsport.com/product_info.php?products_id=334"><img src="http://www.034motorsport.com/images/AAN_CRANK_PULLEY_KIT.jpg" border="0"></a>($225 w/core exchange)

- a pair of wiring harness adapters for the engine bay.. one of them goes from the MAF connector to the air temp and coolant temp senders. Long story, but basically the AAN wiring harness uses shared ground for those sensors and 034 uses shared +. I couldn't flip the polarity because the ground is shared in a few places that risk grounding out the 3.3v supply in the ECU so I cheated and decied to use the unused MAF connector to run a sub-harness.

The other engine bay harness that is needed is an adapter cable (basically an extension cable) that plugs in where the RPM sender used to and extends forward to reach the VR sender for the crank pulley. You can use that exact same sender if you'd like, its a VR type.

Stock coils and stock injectors can be retained, no problem.

The goal of this project was to make an easy way to convert the urS4/S6 to standalone EFI, and also the ability to convert back to motronic in a matter of minutes (It shouldn't take much more than 5 minutes or so to switch between the two).

I don't know if you had a specific kind of epoxy in mind, but you might want to consider potting compound. I don't remember the brand, but they sell this black pre-mixed potting epoxy at You Do It Electronics in Needham that would probably be perfect. It's really thin, so it would flow between the pins easily.

No specific epoxy in mind, but anything non-conductive and that flows reasonably well would be good. Even the cheap stuff at home depot would work I think, it flows slowly but if you let gravity do the work it levels out very nicely. Basically stick the connector facing down and box off the sides with saran wrap or whatever backed with something solid to form a bin for the epoxy to form in.

Black would be a plus for asthetics though. You know if any big name stores carry that kind of stuff?

what's the point of all this? what does 034 engine management buy you?

The nice thing about potting compound is that it's designed exactly for things like this. So it won't get too hot when it sets, its coefficient of expansion should be similar to materials used to make PCBs, etc.

I have yet to be satisfied with 'chip' tuning, not to mention I have upgrades planned that would require me to get a new chipset (GT3071 turbo) and I'd much rather switch to a system that lets me update my fuel and timing maps whenever I want at no additional cost.

<a href="http://www.mgchemicals.com/products/832b.html">from MG chemicals</a> but the stuff I was thinking of comes pre-mixed (which is bad, since once you open it the clock starts ticking).

knock doesn't happen by accident or out of the blue. It occurs due to running too much timing for the fuel quality or boost level. I'm not concerned (BTDT x2 standalone powered cars).

I'm thinking I'd like to wire my IIc the same way. How did you order your ECU connector and where can I find the wiring diagram for my UrS4?

i'm still curious to try it because i know a couple guys who tune these. I'm also looking at SDS efi.

Does the 034 IIc have altitude or water temp correction? The lack of altitude correction worries me with the SDS.<ul><li><a href="http://www.hydraems.com">http://www.hydraems.com</a</li></ul>

altitude correction: yes. There is a provision for a baro sensor.

water temp, yes.

I ordered the ECU connector from the VEMS online catalog. See the post above and click on the picture of the connector, its a link to the catalog.

For the stock wiring diagrams I used my copy of the Bentley. E-mail me if you need them. Once I verify my adapter works on my car it will work on all models of urS cars.

position/connection with 034?

I already have a stage IIC for my coupe. 034 has a dual map feature that allows you to have two complete maps inside the ecu. one map is active when the MAP SEL pin is grounded on the ECU, the other map is selected when that pin is left open.

For me, this means that I can run the ECU in both cars and simply swap the ECU over to whatever car I want to drive. If I need to have both cars running at the same time, no problem, just hook the motronic back up on the wagon.

I think from order to delivery was less than 2 weeks.

I just finished ordering a connector from VEMS. I do have a Bentley so I will get the wiring diagram from it Thanks and I will be watching for any updates on your project.

<a href="http://www.mgchemicals.com/products/12.html">Clear RTV potting silicone</a>

If you use this stuff, you at least have a glimmer of hope should you need to add or change a wire...

9.5 lb pail though.. ouch. I need to get this thing secured soon so I dont accidentally break the pins. I'll probably buy something tonight online.

group buy!!

If I 'finish' (read, at least get it barely running) my v8tt coupe I want to bring that down.

Otherwise It'll be the wagon as usual :)