Join Date: May 2002
Location: Loma Linda, CA
Feedback Score: 1 reviews
The first thing I would do if I were you is try to figure out whether or not this is a random misfire occurring or if it is just affecting one cylinder. You can do that by pulling the spark plug wires off one at a time while the car is idling until you fine the one that doesn't change the idle...sounds like it is cyl #1 so I'd start with that one.
If it is just the one cylinder, narrowing the problem down will be easier than if multiple cylinders are misfiring. At that point, you can eliminate everything except the stuff that is just specific to that cylinder, which would be the compression of that cylinder (i.e. valves not seating right, a blown head gasket affecting just that one cyl., bad compression ring on the piston), a plug or a wire, or a bad or stuck open injector. Also, don't assume your spare injector is good. At this point, moving components from one cylinder to another one by one and watch to see where the problem goes. Once you change a component and the single cylinder misfire moves, then you've just effectively troubleshot the problem.
A multiple cylinder misfire could be a multitude of things, but it sounds like this probably isn't your problem. I'd elaborate but you need to do the first wave of diagnostics before I get in to that.
Excessive fuel in a single cyl miss usually causes black smoke and soot. You are describing white smoke and a misfire under 3k. You also say the spark plug is black and smells like gas. A blown head gasket with water leaking into cyl 1 may look like all gas, but typically you'll get a gasoline smell due to just the misfire AND water, which will also have a heavy gasoline smell. Additionally, the fact that the miss goes away at higher rpms is another symptom of a blown head gasket. White smoke is another indicator. Another giveaway is if the misfire occurs more when the car is cold as opposed to if you've just driven it and start it back up again - if it runs a lot better when it's hot, that is another sign indicative of a bad head gasket.
Check cyl 1 by removing the spark plug and really inspect what you think is gas. If it were me I'd even go as far as licking it to see if it's sweet (glycol in the antifreeze). I bet it is probably antifreeze.
If it really is gas, and the injector is good, then there may be a problem with the grounding circuit of that injector, or possibly even the ecu, which controls the injector ground. Also, a no spark condition can cause accumulation of gas on the plug, as the fuel isn't burning. You can test for spark by taking the plug out, reconnecting the wire to it with it out of the head, and touching it to one of the strut tower bolts (make sure you plug the cyl with a rag or you'll blow yourself up). You should see a spark jumping the gap while cranking.