Just couldn't help myself to a $500 mechanic special, could I? Good shape but has clear coat issue but who cares about that...
Anyway, I love to shade tree work on great older cars. I have learned alot form BB.

I have searched the forum about 240 no starts and seem to be getting close...

Issue at hand is 1989 240 does not start but cranks well. Crank position sensor swapped with know good, fender 25A fuse and connection good, AMM good, gas in tank.

Car will sometimes run at idle for short time and then dies.

I suspect ECU which is #556 (cali car).
If the I jump fuel pump relay socket 30 to 87/2, the pumps turn on but no start....
If I put relay back into socket, and then jump fuse 4 to 6, car starts great and revs nice, but if the 4 to 6 jumper is removed it will then slowly die.

Intank pump and main pump run and verified by removing fuse 4 and left side jump to 6 and right side jump to 6.

I have a 92 740 turbo. I want to take its ECU out to check on the 89 240. I ASSUME THIS IS OK??

If I need a ECU, which ## options will work for #556 swap. I will look at pick and pull and ebay.

Thanks in adance for BB community

Rob
Winters, Cali
92 745T
90 MB 300e