I am completing an engine swap on my 86 745 GLE. I took the engine from an 86 244DL. I have everything hooked up but I’m not getting an rpm signal, spark, or fuel. I thought I just wasn’t getting fuel so I sprayed brakklean in the intake and nothing. It sounds like it’s getting compression. I’ve never had trouble with the tach not working. I’m stumped. Any useful tips are very appreciated

 

Did you use your old engine wiring harness from the 740 - or was the one from the 240 EXACTLY the same?

 

the 88 240 harness is definitely different, it uses an entirely different ignition system, has the distributor in a different place, etc. both cars were LH 2.2 injection, but the 240 used a 'chrysler' ignition system while the 740 used a Bosch system. also the 740's got a RSR relay powering the injection, the 240 didn't.

the 88 240 *engine* mechanicals should just drop into a 88 740, you can either plug the 240's side distributor mounting hole and open the rear camshaft distributor opening and use the 740's distributor, or just rewire the hall sensor, and use 240 spark plug wires and the 240's distributor.

if you're getting no spark and no injection my first guess would be that hall sensor and its wiring.

 

I literally dropped the block from the 240 in my 740 and swapped the 240 head for the 240 head so I could use the Bosch distributor and used the 740 wiring harness

 

i swapped the 240 head for my old 740 head so I could use the known good distributor. I didn’t change any of the wiring. I literally dropped the 240 block in and put my 740 head on and plugged everything back in. The hall sensor is in the distributor right

 

yes, the hall is in the distributor on LH2.2 cars up to 1988 (and 1989 turbos). I would check the wiring to that hall sensor, as thats the source for all timing, ignition and fuel injection.