Shutting off problem

[4Devils30]

I have been having a problem for a while now with a stock 1990 300ZX 2+2 Manual transmission, with about 88,000 mi. The car has been very rarely used the last 15 years. I had an incident years back where I hit a road hazzard with the passenger front wheel. The hit was enough to lose the wheel well liner. The car stalled out but started right back up. I started noticing that whenever the RPMs were over about 2500 and I pressed the clutch, the RPMs would drop below idle and the car would stall. It starts right up without any problem. It doesn't happen at low RPMs. If I give it gas for a couple seconds as I am coasting to maintain idle RPM, I can avoid it stalling.

The car has been driven about 2000 miles in the last 10 years but hopefully soon, I would like to get back to driving it more regularly. I am not mechanically inclined and can only do minor work myself. I want to take it somewhere to get it fixed but I would like to go into a shop with some idea of what may be wrong.

Any input would be appreciated.

[DCaff300ZX]

First off, we need to know where you are located to have any chance to perhaps know of a qualified Z32 mechanic.
Next, losing the wheel liner in such a way hints at the chance the air intake was also damaged and/or the air box, or that the air box was dislodged/damaged to expose the MAF.
Having air flow across it can cause such an issue as you indicate, although there are other possibilities that would be diagnosed best if there are any ECU codes/check engine light on.
If you are mechanically inclined enough to change the air filters, then you can check to see if this is your problem and perhaps avoid a trip to a Nissan dealer at worst, or a Z mechanic.
If you can, when you unbolt the front cowl cover to expose the filter box assembly be sure that the box is undamaged and it is in it's correct place, and that the two "arms" extending into the wheel wells in front are also in place and one not perhaps jammed into the air box.
Your solution if there is damage or otherwise an exposed MAF may be to find a way to replace the air box correctly, and have the MAF unit inside the box be sealed from the outside airflow.
Hope this helps, and that if you post your location we can suggest a Z32 mechanic if needed.

[4Devils30]

Thanks for the info. I will be moving to the San Jose Bay area. The car is coming at a later date so I will use your advice when I finally get settled.