I noticed the other day that when my 1993 Pickup is idling after its warmed up the idle will sometimes start to surge. It kind of sounds like there might be a vacuum leak somewhere but I checked all the hoses on the intake and theres nothing noticeably wrong. And also, when im driving slow in 1st gear, at around 2700 rpm the rpms will suddenly drop to about 2200 and then pickup, and then drop again like Im feathering the throttle. It does the same thing when I just rev it up in neutral. Its super annoying and I need to know how to fix it.

Other than that the truck runs fine. I replaced the TPS and someone told me that could have been adjusted wrong. Im not the one who adjusted.

 

Your TPS needs to be adjusted, you need a set of feeler gauges and a voltmeter http://personal.utulsa.edu/~nathan-b...93throttle.pdf