Ubernater202
New Member
Hello, I have a 1987 Ford Ranger 4x4 which originally came with a 2.9L. We did a 4.0 OHV swap out of a 91 Explorer. The issue I’m having I have not seen on this forum (either I overlooked it or it’s not there I’m not sure) but when you first start the truck it revs to about 3000-3500 rpms and then comes down to 1500 rpm it never goes below that. I’ve checked everything I know to check. MAF is good ICM is good. All my connections are good. The throttle cable isn’t getting stuck or anything and I just can’t seem to figure out the problem with this truck. I’m still young and inexperienced in the diagnostic side of things so there are likely many things that I am overlooking so sorry in advance. I think it’s a vacuum leak but I’m not sure how since everything is plugged and/or new lines. I normally wouldn’t really have a problem with this but that many revs on startup just can’t be good for the engine in terms of longevity! Any help or advise would be helpful, thank you!
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