Intermittent No Idle
 

I'm in the midst of taking my 300E out of moth balls. I ran it briefly a few times in the last few days to move it around, check the a/c and such. It refused to idle except for some times when you eased the speed down to an idle. This led me to think that I might have a sticky flow meter.

I found a broken vac line from the air filter breather hose that goes to a diaphragm of some sort. I fixed that and while I had the air filter off I checked the flow meter for smoothness and it all felt good.

I then drove it to town to wash it and wash down the engine compartment real good since I will probably be replacing the a/c compressor soon. Once I got a few miles down the road and stopped at a stop sign it was idling fine. Several times rolling down the highway I kicked it in neutral (manual transmission car) to see if it would idle and it idled just fine. I got to the car wash and it idled just fine. This led me to believe that the problem was only a cold idle problem.

It ran fine and once I got back close to the house I let it coast in neutral for the last quarter mile or so and it idled fine at first, but then died about the time I turned in the driveway.

I plan on checking fuel pressure next. As history, I replaced the coolant sensors not long before it went in moth balls. As I recall this problem was begiinning about the time I put it in moth balls.

Any ideas are appreciated.

How about these for ideas:

1) idle air control valve and its 2 vacuum hoses;
2) deceleration micro switch
3) throttle valve switch
4) airflow sensor position indicator
5) crank position sensor