I have a 1988 DX 1.5 with throttle body injection. At idle the car surges (500 rpm for 5 sec, 2000 rmp for 2 sec, 500 rpm, etc) and the exhaust is extremely rich. I have replaced the O2 sensor and cleaned the idle air valve but that didn't help. There are no vacuum leaks. Anyone else out there had this problem?

Thnx,
B*

 

sounds like a map sensor issue because of the black smoke and the idle surging.

 

I got that suggestion from another honda guy too. Also got the suggestion to change coolant temp sensors (from one of my corporate account mechanics). The logic here was that if the coolant temp sensor is telling the ECU to stay in warm up mode, it'll load up on fuel when the engine actually gets warm