2.7 in early car but no tacho

[porschetub]

Hi all,have engine in car and running ,started easily after priming fuel system .
Have exhaust to modify as centre box is a cat converter which I don't need and is probably blocked anyway after 21 years.
All appears ok @ this stage but my tacho won't work ? does this work of the coil or the speed sensor ?,hope someone has a quick answer ? ,cheers

[oliver88]

Just did a transplant myself...1989 2.7 into a 1986 chassis...tach had to be connected from the DME...green/yellow wire if i recall...

[rlofgren]

i put an 88 motor in an 84 chassis and the same problem, tach doesn't work. is what you describe as a fix different from the normal connection to an 84 chassis wiring harness?

[porschetub]

Thanks ,yes I traced back with tester and found green/yellow wire,this was on or should I say attached to main loom with its own "'mystery"8 pin plug.
Haven't wired up as I have other probs .

[Warwood]

I did this swap as well a 85.5 2.5L into an 84, I even cut the same hole as you did. Ran into the same problems. Thinking back on it; in the case of the S1 body cars going Megasquirt and making a new wiring harness is a better option than cutting holes. But for that matter almost as easy is getting an OBDII system out of any german car and refitting it to your car is a much better plan. Then have some one burn a chip and tweek it from there. For instance my 92 Jetta has a 98 2.0L runing OBDII and it just kicks ass. DME is So '80's IMO.