Hello,
Has anyone ever changed the computer on your Bronco II? If so, did it
fix your problem? I know I said this before but my 1989 B2 2.9V6
auto has a miss I can't find. It idles great (a little fast). But when you rev
it up it stumbles and the check engine light flickers than goes off. It
has a new fuel pump,fuel filter,plugs,cap,rotor,TPS,coil and complete
new distributor with TFI module. I've checked and cleaned most of the
grounds I could find. I've checked the timing which is correct. I also
checked the fuel pressure at the fuel rail and it holds a steady 35 PSI.
Any ideas before I pump it full of buckshot.....
Thanks for reading....

 

As a last resort go ahead and replace I assume you have checked the codes.

Some guys by new moduals or some get them from the junk yard, if you have exhuasted all leads what do you have to loose.

 

There are usually a few used ECM modules for sale on Ebay, also I have had two new TFI modules installed that were bad out of the box. The mechanic that installed it spent two weeks trying to chase down the problem, before replacing the new one. I just had a factory rebuilt engine installed, and they put in a new TFI. Guess what it was doing when I went to bring it home? That was two bad TFI's out of four installed.
Just wanted to share that info.

 

what does the fuel pressure do when you rev it. Also have you checked for any Vacuum hoses that have any cracks or holes.

 

No I haven't checked the fuel pressue when it does this. Thanks for the reply

 

oh another thought make sure your coil isnt shorting out (to ground) I had a tac hooked up and one day it just stopped running come to find out the tac was shorting to the ground and keeping the coil from working

 

Have you checked/replaced the MAP sensor?

 

I checked the MAP sensor and it works fine. I pulled the codes today and came up with a 51-coolant sensor and a 98-hard fault? What's hard fault mean? How do you check to see if the coil is grounding out?