Re: Power Problem........
There are several sensors that affect the cold running and warm running of the EFI on the 351. I'm assuming your 89 is the same as my 88 or at least pretty close.
I replaced the Throttle position sensor, the EGR position sensor, the Air temp sensor, the Water temp sensor, replaced fuel filters and sprayed a couple of cans of injector cleaner down the throttle body and had the injectors cleaned when it was all done.
I was trying to fix an over-rich problem where I was getting way too much fuel after things warmed up (and making it fail a smog check) I was told the feedback of the engine can try to fix alot of things and that any one sensor out of whack could confuse things and cause a very rich or a very lean mixture. I decided to just replace all the sensors that were 20 bucks or less each rather than spend a weekend troubleshooting each one or paying someone to do it a 40 bucks an hour.
Anyway, after I replaced all the sensors the smog problem went away. I had the injectors cleaned (had a coupon, never been done...) and it seemed to run abit better still.
If your doing this yourself, the factory shop manuals are really good, expensive but very detailed.
99 4Runner (wifes grocery getter)
88 Bronco ** SOLD **
01 TJ Arriving in August