Driving 40 mph car quits, mechanic says it has a timing issue

YOU NEED A NEW MECHANIC ASAP. It is an elecrical problem, you have a sjhort somewhere. Main computer could be bad or need service. Your mechanic probably broke it or shorted it out.

you mean to say the engine is missing?

test the front end completely. You must go to the mechanic, the tires specifications you must see

God bless you

Yes , your neon has a interference engine , it will bend valves , put holes in pistons .

Could be a wheel, tire, or axle shaft.
You could rotate the tires front to back and see if the vibration moves.
If it does the problem is one of the tires or wheels.
If it stays in the front, its probably one of the axle shafts. It could also be a hub bearing or something loose in the suspension. But a loose suspension part would normally show up when you hit a bump rather than on a smooth road.

Don't start replacing parts until you know for sure what has failed. I would say that the PCM is not the problem here. As far as the gas pedal is concerned, it sounds like you may have a broken linkage at the pedal, these trucks do not have a cable but only a rheostat that the computer reads.
The tachometer and speedometer problem could be a bad cluster.
You need to see a good mechanic to get a diagnosis.

sounds like your CV joints have died, if its to the banging and crackling stage,, they are shot, and need replacement right away before more damage happens ,, Not knowing where you are located makes costs hard to estimate,, at Autozone (I'm in California) the cv axles for your vehicle are 69.00 plus core charge,, ( just give them the old ones and this is deducted from the total cost ) I recommend you do both sides at the same time, I got lazy one week, and had no time, or I would have done them myself, so I had a local mechanic do them for me on a toyota camry,, and he charged me 350.00 total,, parts and labor,, if that gives you any idea ,, Hope so,, Good Luck,, if you need anything else just respond to this feed and I'll assist you more

probably the timing belt broke, there should be inspection in the cover or the top half should be removable for inspection

If the timing belt has broken it's more than likely you have some valve damage.
Not the end of the world.
Options are...Head overhaul, inc valve replacement.£££££££££
Or find a complete Cylinder Head in a breakers yard and swap.

I read this over and over on these vans, same problem, you will need to have the trans overhauled to correct this problem, a $3000 job on this particular car.