Hi All,
Got an '87 GM that has a "slight up/down idle" when first starting. Only lasts a minute or so and then is fine. Sometimes a slight stumble from a stop. Likeliness culprit be a TPS or IAC?? Car has a little over 121K and have had it from brand new. Never remember changing the TPS but did the IAC a couple of years ago. Forgot to clean out the ports before install, though. Boy was that dumb!! Let me know your thoughts!! Thanks....MB