Hi. 1991 240 Base w/B23F (Red) Engine. So what I thought to be an alternator issue was only a bad belt or bushings which is good but now...it wont start. First off, when trying to diagnose the squealing problem, I overtightened the belt (screeching for 2 seconds, a single backfire and I stopped). Checked, reinstalled w/new bushings & belts & fixed squealing issue. Now no start. It just turns over and over but doesn't even want to catch. Check fuel pumps, replace in tank pump (which has been out for a while). Both pumps working now but still no start. Clean fuse box & replace all fuses with new ones. Nope. Starter/Alt./Battery all tested fine & working. Plugs getting spark. Open oil cap/timing belt cover & belt is still on & turning freely. I go to check the OBD-1 Codes and #2 gives no code reading whatsoever- hold the button 1-3sec and just stays silent. #6 gives coolant temp sensor (which I also knew I had to replace for a while). What does it mean if I do not get any codes from #2? Where to go from here? Maybe jumped timing (but doesn't even cough or sputter at all?) ECM/CPU (the timing of this just "going" would be strange no?) Thanks...I am at loss.

 

well, if you're not getting /anything/ out of the #2 OBD port, I'd suspect your ECU died. or the wiring is munged. or the main EFI/fuelpump relay is kaput (that relay module actually has TWO relays in it, one powers the ECU and injectors, and the other side powers the fuel pumps).

btw, your engine is a B230F. the B23 was an earlier version, from circa 1983.