1985 Ford Ranger 2.3 starts and idles good. But when put in gear dies until it reaches full temp.

My work truck run great until you put it in gear it would die it jerked hard in reverse like it was missing . And it was the shift telay

I am not sure..sounds funny though, may be the battery.

the first thing i\I would try is to replace the Oxygen sensor...this happened to me on my 91 F150 pickup and that cured it..

88 ford ranger 2.9 surges buck down when take off in first gear

well youre in the right area check with the dealer there may be a sensor for the cold mode like a choke that is not working

The mechanic should check on the idle .Because the Idle of the truck is adjusting by it self . That causes the truck to stop .check the Idle then lock it up to so that it will not adjust until it will make the truck stop .the main reason why the truck stop and pressure guage going down steadily is that no fuel enters the fuel pump when it adjust Idle by it self . It adjust by closing way or blocking the fuel to pass and go to the engine.then the engine dies .

with what you have replaced,your comment about your great service,I would say it is very possible.And 395,000 congrats!!!!!!!
Fords go through the least amount of ECM than the other american made vehicles.

check that crank sensor

Replace you fuel Injector pump and check for any bad or clogged injectors. make sure idle adjustment screw is properly set

have someone check it with a code reader to determine reason for the check engine light. it could be the source of your problems. the check engine light comes on so you know there is a problem. with most vehicles becoming more complex, the code reader can be used to pinpoint many problems that are not detected otherwise.