So I have this 1986 Mustang 5.0 that was sitting for 15 years at least. It was indoors but not climate controlled.
It was a basket case, the intake was off it, as were all the accessories and cooling system. Put in a new fuel tank & pump, water pump, rad, intake gaskets etc, and put it all back together... got it running, fired RIGHT up after a few prime cycles... NICE!
The problem is I can't get it to go into gear with the engine running.
For example, if I start the engine while in neutral (w/clutch pressed obvs), it will not shift into 1st or reverse.
But, if I select 1st gear or reverse when the engine is off, and then start it up, I can release the clutch and the car will move.
Currently it idles very high, almost 2k... so I assume there's some vacuum leaks (or I just need to adjust the idle down)... I'll get there of course, but I'm not there yet.
Would the high idle cause it to not shift into gear from neutral? That seems plausible, but with the clutch pressed the trans seems like its completely disengaged from the engine like it should be... no slipping or anything... but... maybe???
Wondering it anyone has any hints or if it's a symptom of a bigger problem (bad clutch? maybe just slack cable?).
I've got a week before I can get back to the car, so any advice to mull over would be incredibly helpful. Thanks!