I've got a 97' ranger with a 2.3L. When it has sat for a while and cooled off, for example over night, when you start it up it runs and idles smooth as long as you don't get it above three grand or so. Once you do and you let out of the gas it starts to miss. I checked the vacuum when it is not missing and when it is. Good idle=17" of vacuum -Rough idle=about 15" of vacuum but when it is missing the vacuum fluctuates by about 5" or so. When it starts to miss, if you let it sit there and idle it will slowly fade away. Even if you let it warm up it will still do once or twice but not as bad. Also once it has done it once or twice it won't do it any more. Has any one else experienced this problem?

 

rngrman, I don't know the answer to this problem, but i would like to. My grandfather has exactly the same issue, and I don't know how to solve it. It's like the air shuts down, but the fuel maybe either continues to dump, or the fuel isn't burnt out of the cylinders fast enough. Whatever the problem is, it drags down the whole motor...the belt slows down, it starts pulling on the battery, and misses bad, and then recovers. at any rate, I'm interested in what is found out.

ckb

 

rngrman, I've been searching the net and the problem is leaning toward the Idle Air Control Motor or Valve...Google it and see if it souonds familiar. It pretty much describes my problem to a T.

ckb

 

I would change the fuel filter first then go ahead with the idle air control motor or valve...my bud had almost the smale proble and we changed the the fuel filter and its rums nice.

 

Dude sorry i just sounded like a idiot ha...didnt read it over. but you can understand it.

 

I have the same problem too - I've changed fuel filter, IAC, plugs, wires and a bunch of other stuff, and I have the same kind of issue. Do you throw any codes? I haven't tested the coils yet but tested a bunch of other stuff and I'm still scratching my head.... I would recommend switching the fuel filter as a first step.