'89 3.0 here...

running on 3 cylinders right now, happened all of a sudden. Cyls 1, 3 and 4 are not firing. So far I've got spark to all 3, and I'm going to do a compression check, even though I'd be surprised to lose compression on 3 at the same time (and on different sides). Going to check the ECM as well. It never overheated. #4 injector connection looks good, can't see 1 or 3.

Going to be away from my computer for a while, but I'm going to check back if anyone has any suggestions......

 

update...

got 150-160 psi on all 3 cyls.
traded out an ECM from a '90 3.0, and no difference.

So, in short, I have 3 dead cylinders. All 3 have compression. All 3 have spark. That leaves fuel...so what would cause 3 injectors to go out at once, 2 on one side and 1 on the other? (assuming it is injectors, thats about all thats left, right?)

Is there a rev limiter? If so, where is it? And is that something that would "freeze up" or something? I am out of ideas, other than start tearing stuff apart.

 

Yeah injectors seem like a idea to check

 

I'd lean at a wiring issue.

 

A loose injector wire

 

I'd also say it's a wiring problem.

 

x3 on the wiring. Look at your FSM and see what those 3 cylinders have in common.

 

I did, but other than the ECM, I don't know what they have in common. So I guess I'll start taking things apart.