Hello,

I think I can answer your problem, I'll try to make this short.

I have a 84 245, two years back I noticed a lot of slop in the distributor shaft, under the timing light, the mark would jump around. I ask the question here about what distributors I could use, and was said that I could go up to 88.

So I picked up one from the pick-n-pull and swapped it in, now here is the act that took me down the wrong path. At the same time with the distributor out of the way I also removed and cleaned the idle control valve and the throttle body.

After starting it up I had poor idle, stalling during braking, I was unable to set the base idle to spec. When I would ground the wire that takes the ICV out of the loop to set the base idle, I could turn the throttle screw all the way in and not get the idle down low enough for spec.

It was as if the engine had suddenly developed a bad case of blowbye. The list of things done is as follows.

ICV cleaned and replaced
throttle body cleaned and replaced
TPS adjusted and replaced (again & again)
ECU swapped from 503 to 510
checked for vacuum leaks (again & again)
relaced oil trap and its O-rings
ran the Bentley diagnostic test, pin for pin at the ECU plug

STILL THE SAME!!!

Then someone asked the 83-84 distributor question here again about a month ago. And this time someone said the 83-84's were hall effect, and the 85-88 were something else can't remember the term, and he thought they were not compatible.

So I went to the pick-n-pull found an 84 with a solid distributor, and made the swap.

My car now idles perfect and does not stall when coming to a stop. Because I had removed the trottle body and the ICV at the same time I chasing my tail all this time and had overlooked the distributor change as being the problem.

--
Bruce S. near D.C.