Hello my name is Noah, I recently purchased a 87 Sport FC that I recently got running. It has an issue where it idles around 1500-1700rpm surging up and down slowly. It has all new vacuum lines and checked for leaks but did not find any. Tps is tuned almost perfectly. A side note that the car is hard to start sometimes have to turn it over in three different intervals, after warming up it starts instantly(Still with the surging idle of course). Any help would be appreciated!

 

welcome to the board.

you can check the sensor at the back of the water pump housing. it has probably gone bad.

 

My tps caused a surge like this once