1987 944 ECU Installation Help

[Doug in Detroit]

I need assistance on the installation a Motronic ECU into a 1987 Porsche 944 (non-Turbo.) The vehicle has been out of service for a couple years. I went through everything, everything was operational (turning over, spark, fuel injection) but the vehicle would not start. In doing research, it seems a likely cause is the ECU. I just bought a 944.618.121.04, and need the location of the ECU.

1. I know it is on the passenger side. Exactly were? Under the front carpet under the wooden firewall cover?
2. Pictures would be helpful (I know this is a long-shot.)

I could tell you the history of the car, the repair attempts and a very good horror story. I got a bid fed up with it, and mothballed it in the garrage. Now I'm willing to try anything/everything to get it running. I'm hoping it is a simple fix, but if not, any and all help is appreciated.

-Doug

[SoCal Driver]

Detail the tests you've gone through to determine it's the DME/ECU.

Is this a 944S four valve?

You should see voltage at the coil and at the injectors with the key on. If no voltage at the coil it's the ingition switch. If no voltage at the injectors but voltage at the coil, it's the DME/fuel pump relay.

If the above is good but you have no spark at the coil/plugs then it could be the DME or the reference sensor on the back top of the engine.

[joshmo144]

Can a early na or turbo cam be used in a late na?

[944 Ecology]

Originally Posted by joshmo144

Can a early na or turbo cam be used in a late na?

Yes, it can, but it will produce less power.

[Ga 951]

to answer the OP
Yes the ECU is under the wood panel on the passenger sidewall. Remove the wood. Unplug the ECU, remove the bracket and ECU. Pretty easy.
I hope that is the real culprit, but that is how to replace the DME (ie. ECU)