Thought I would post an update now that I have recovered (my H1N1 turned into pnemonia, which was fun). Haven't had a chance to really do much yet on the car.
I am becoming more convinced that this is a solenoid-operated vacuum issue. The car will be down on power when it acts up, the vacuum gauge will swing much more than normal with small changes in throttle position, and the transmission will hold a lower gear longer (as if it thinks I am giving the car more throttle than I am). It does not smoke or smell, which would indicate a too rich mixture. I think it is simply allowing too much air into the mixture, leaning it out.
A few times, the car will spontaneously switch to normal and stay that way, after it has warmed up well. It has done so a few times driving down the freeway, with no change in pedal position. The car just kind of "clicks" and starts accelerating, then I look down and notice the vacuum gauge is normal again.
So I am thinking this is an airflow issue, instead of a fuel issue.
Anyway, I will look into it more this coming week.
Thanks guys!
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1990 560SEC
1988 300SE
1978 928 euro S engine, big brakes, and more
1996 Suburban TX shark rig
1988 Suburban Pacific steelhead rig
1992 300 TE (recently totalled
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