Car is a 90 C4, option code CO3. Mabey red car makes a difference Except for Porsche update, I have NO reason to believe it is not the original DME 911.618.124.04 Ck eng function fully operational.

 

Mine too is a 90' C4 C03(CA Option) and it has the older 964 DME number. Are you sure yours was never swapped out? According to all manuals/tech information my part number is proper for that year. Not saying that yours is bad. As a matter of fact I would like to be able to read out the codes from my DME.

 

I have all receipts from PO. No indication of a change. I was also surprised at the "911.XXXXXX" prefix. Interestingly, when I was having running problems, I looked at a friend's 92 C-2 brain, with the idea of swapping for a test. His brain had a "964.XXXX" prefix- and his light works fine. We did not trade, because I wasn't positive that they would interchange, and I didn't want to risk screwing up my car or his. Perhaps Adrian has a thought? (When does he NOT? )

 

Dear Horst,
This does not require any thought. We do this type of thing all the time with our aircraft, except we change the part number but your dealer made a failure.
Your DME has been completely changed with a software update from Porsche. You have the equivalent of a 964 618 124 03 in your C4. They just did not change the part number on the outside. I suspect that the dealer just did not bother or forgot to finish the job off properly. Even our mechanics do this sometimes. It is one of my jobs to fix these things.
You should no longer quote your old part number because this is no longer installed. It does confuse people Horst. They think because you keep quoting this old part number that theirs should work as well. It will not because you do not have this part number installed anymore. To use my normal words Horst, "your first post is not entirely accurate". Only the box and the hardware is original. The heart and soul of the DME, the software, has been replaced which does change the part number,
Ciao,
Adrian
911C4

 

oh. Just curious. what was the original "911.XXXXX" brain used in?

 

Dear Horst,
I am not sure what you mean. The Carrera 3.1 "Brain" provided the base for the development of the Bosch 2.1 System installed in the 964s. The 928 developments were also very helpful. The 928 uses a hot wire mass airflow sensor. LH versus the L for the 964.
However all that said, the differences between a 3.2 Carrera system and the 964 system is like comparing an old 4.77MHz IBM computer to say a 386. The Bosch 2.1 compared to the 993 (1996 and up) 5.2 system is like comparing a 386 to a Pentium II.
Ciao,
Adrian
911C4