Hey all, my 95 Del Sol Si with the D16Z6 has developed a startup idle issue I've never experienced. Hoping someone has ran into this before. Frequently when I start the engine, doesn't matter if its cold or hot start, it will sputter for a few seconds and then smoothe out and idle\run fine. I've swapped spark plugs, fuel filter, distributor cap\rotor, air filter, and fuel pressure regulator. I cleaned the throttle body and fuel injectors (replaced orings and seals while they were out). Timing is spot on. I might would think distributor but I replaced it a little over a year ago. It's not a "surging" like it would if was the IACV but more like a sputter from fouled plug(s). Any D16Z6 veterans have any ideas as to whats going on or something to check?
Since I originally posted the thread, I have done some researching. I have read that a faulty throttle position sensor or MAP sensor may be the culprit. I have since given the MAP sensor a good cleaning and replaced the rubber o-ring. After a couple of starts, it was idling smoothe. I will update again after I have made several cold and hot starts to verify if this has fixed the issue so that if someone else has this problem it may be of help.
Update: Looking like a head gasket issue.
Update: It was definitely the head gasket. The ONLY symptom the car showed was a slight, consistent loss of coolant and air bubbles in coolant reservoir. No sludge in oil cap, no steam or condensation out of tail pipe. Spark plugs were not 'steam cleaned'. Maybe this will help if someone else experiences the same problem.