Swapping 944 ECU's - will not start?
 

88 944 will not crank. Changed with new parts: plugs, wires, rotor button, distributor cap, coil, fuel cartridge, fuel relay, speed sensor, mark sensor. 12V Hot off the coil and at all plugs. The only thing I know left is the alarm module & ECU. This ECU is BOSCH 0 261 200 086 /// 944.618.121.05. I have another 87 944 with an ECU that is BOSCH 0 261 200 077 /// 944.618.121.04. Does anyone know if it is o.k. to swap these two ECU's? Going to do the alarm module bypass right now. Thanks for any help or ideas!

Bypassing the alarm system did not work. So I crossed my fingers and swapped out the ECU's. Now it starts and runs like normal. The problem is my ECU. O.k, the only way I know to troubleshoot the ECU is to heat up any cold solder joints, check for cracks, etc... If I do those tasks and it still doesn't start, I am going to swap out the chips in the ECU's and see if that makes a difference. Does anybody know where I can get schematics for the ECU's and try and find out what the difference is between the circuit boards?

Is the engine turning over?

sorry, went back and read the whole post(duh) as to schematics, I've never seen one perhaps someone else here has seen one.

:) Pulled the boards out of the ECU. Took out the soldering gun, heated up the tip and got happy on the board with some hot new solder. Pulled the chip out and reseated it in the plug. Closed the ECU back up and plugged it back into the car. Turned the key and she started up as though there has never been any problem at all. I am disgustingly happy! 6 weeks of downtime and about $500 worth of new parts = one idiot that now knows how his ignition works. If the rest of life was this simple I don't know what I would do!SmileWavy

I think I saw some schematics for later dme's on FR Wilks site.

PM sent.

'87 and '88 944 have different engines. The '88 is higher compression. Therefore the '88 DME is specific for that year only. You can swop a '88 944 DME with a '88 924S though.

Thanks Glademister, Outback & Jeff! I went to http://www.frwilk.com/ and looked at some of the info there on the web pages. Great site & WOW perfect bodies! I downloaded the schematics for the 911 and 951. I am going to get a replacement just to have for future problems. I was really surprised with my ECU. The box was clean as if it just came off the shelf. The boards looked nice, a little fading, but no damage or deterioration to any circuits. No visible corrosion. I don't know if it was just reheating the solder joints or reseating the chip that fixed the ECU. Just extremely happy that I didn't have to try and find another ECU. Cheers & Good Day, Rattlesnakeracing

No wucken furries.

Mmmm.....FR Wilk's grid girls..............

Cheers