Difference between 944 DME ECU's.

[alantica]

Originally Posted by The Glademister

The '88 944 NA and '88 924S have the same DME but it is specific for that year. Earlier DME's will not work in an '88.

DME Info about '87 / '88 NA:

Currently running "87" 944.618.121.04 DME in my "88". The part number for the "88" is 944.618.121.05. So, if anybody with an '88 .05 DME craps out, you can use a .04 DME, even though the '88 is year specific. Please note that this does not mean "earlier" as in pre 85.5.

The .04 has the short chip and the .05 has the long chip. I have not tried the .05 in the "87". The only reason I am running the .04 is necessity, since the "88" is a daily driver & is currently TDY till this weekend. I have a "new" .05 DME that I am going to install this weekend when the "88" comes back from TDY.

I don't know what the actual electronic output difference is between the two DME's. There are different chips installed besides the pop out chip, but the boards are the same. If someone could point me to exact schematics besides the PET on FRWilk it would be a great help.

Also, since the BMW's (or other european autos) use Motronic DME's, are any of the boards the same as in Porsche's? What I mean by this is not having the exact components, but the same board. It would help me understand the engineering and give me greater access to research resources. My theory is looking toward the future, pulling boards & swapping out soldered chips. Any electronic junkies out there will know what I'm talking about - the actual electronic theory which is most likely proprietory to Motronic.

Hope this helps Memoriter, not trying to hi-jack your thread!

Thanks in advance!

[memoriter]

Atlantica,

I think you're having the same idea I am. I was contemplating taking a look at my friend's stockpile of BMW E30 and E28 Motronic computers to see if I could repair mine with components from those.

I read online, some people have swapped their bad 944 ECU with a BMW and simply changed their EEPROM chip. I'm thinking the M30 engine should have a similar Motronic version, so if I can swap ECU's, it would probably one of those.

Speaking of which, does anyone know of any swappable ECU's? How about a VW or Audi model that works?

Like a complete moron, I missed an amazing deal to buy a 924S DME ECU with the exact part number as mine for $10.45 on eBay, at around 2:30 this morning. I'm man enough to admit I wept a little bit over that. Of course, that was after I threw a silent fit for about 15 minutes.

[Johnysecret]

Hello everyone! I'm new at this site and was wondering if anyone would have an answer to my issues, I have a 1986 944 turbo but all the sudden my engine died on me and all my gauges went dead, now the car will not start any more, if it did will die on my after 3 minutes or so, I keep cranking it but everything is dead on my dash and car will not start could this be my DME computer? I have replaced all new fuses and DME fuse with new and everything seams to be ok that's why I'm thinking could my DME computer be the problem?

[findingmulder]

Hi everyone, have an 86 non turbo here. My car starts sometimes. When it doesn't, which is about half the time, it has no spark and no fuel pressure at the rail. When it does, the psi at the rail is 38psi, and the MAF is functioning correctly. A local Porsche mechanic suggested that I change the ECU, so this is my first day of research.

[944galore]

Ok so I had a no start issue as in the original post. I thought it was the DME. I read somewhere to disconnect an injector and try to start the car. When I did that the car started. It was the fuel pressure regulator. An easy and cheap fix, Autozone $86.

[944guyva]

I have a good ECU, Where about in W. Virginia are you located. I am just over the line in Virginia if you aren't to far We can get togeather so you can try the one I have.