My son's 02 Protege quit running on him as he was driving. He said the engine seemed to just start shaking and then the car just quit. It turns but does not start. We're getting codes of P0401 and P0340.

I removed valve cover and inspected the timing belt. The belt appears to be in good shape.

Any suggestions?

 

Sounds like your camshaft position sensor died on you. Check the plug and wiring leading to the cam position sensor. This sensor plugs in on the left side of the valve cover, toward the front of the valve cover, it's the only sensor there from what I have read so you shouldn't miss it. The P0401 could mean your EGR pipes/ports are plugged up too so a good cleaning of those may be in order as well.

 

Today I took things down to exposing the timing belt. I found that the tensioner spring came off and was jammed in between the gears on the crank shaft and the timing belt. Not too suprisingly, the timing was also quite off. Upon removing the tensioner I found that the hole for the spring was elongated and was about 1/32" from being completely worn to the edge. I'm not too imperessed with the tensioner design.

 

If there is enough room you could drill out the hole, thread it and put a bolt in it with lock-tite. Then you could drill a proper size hole into the bolt.