Mitsubishi Repair: 1999 Galant GTZ Timing Belt not turning, cylinder misfire, cam sensor

Question
Hello, I am trying to diagnose a problem with my brother's 1999 Galant GTZ sedan with 3.0 V6 and automatic.  He was driving home from work when the engine began to lose power on a hill.  He pulled off to the side and the engine was running so rough that the car shook.  He shut it off, waited about three minutes, restarted it with the same bucking issue.  He attempted to drive to the top of the hill but didn't make it but 200 feet before the engine quit and would not restart.  His check engine light came on and I found a P0300 ( Multiple cylinder misfire ) code.  The battery was weak so I charged it.  I also took off the front timing belt cover.  The belt appears to be intack and has tension on it.  I tried to start the car and got a new code, P0340 ( Camshaft position sensor circuit malfunction ).  Since the cam sensor is in the distributor, I bought one of them.  I removed the cap and rotor ( with a lot of difficulty and removal of the battery and tray ) and noticed that the rotor was badly burnt and actually had some metal missing.  HOWEVER, before I took everything apart, I asked my brother to crank over the engine to see if the distributor did turn.  When he cranked it, the distributor did turn, but the timing belt did not.  Now for the questions.

Can I inspect the timing gear on the crankshaft without removal of the engine?

Could the key on the crank gear have broken and the is now just spinning?

Or... my brother said he smelled something electrical burning when he opened the hood.  I am hoping and thinking that maybe some teeth ripped off the belt and "smoked" it.

And the ultimate question... is this engine a clearance engine, or do the pistons SMASH valves when the belts let go?

Thanks.

Donnie


Answer
Donnie,
You can check the timing gears without removing the engine.  Though to get a good look at it, you may have to remove an engine mount to you can lift or lower the engine to be able to inspect the gears better.

Also, it sounds like you got the P0300 ( Multiple cylinder misfire ) code dude to a burnt out distributor cap and/or router.  This is not uncommon on a 7 year old car if the cap had never been replaced.  The P0340 error code may have been seen because the crank angle sensor thought the belt skipped timing due to the distributor cap failure.  The electrical smell was most likely the points on the distributor cap burning due to arcing being produced.  For a belt to produce odor, there would have to be rubbing or some kind of friction.  And excess friction usually causes a noise as well.

What confuses me even more is that you mentioned you saw the distributor turn, but the timing belt did not.  From my understanding on that engine, the distributor turns in relation to the camshaft.  And the camshaft turns because the timing belt goes around it.  So, for the belt not to turn but the distributor to turn doesn't seem right.

Most Mitsubishi engines are interference engines.  And I believe the engine in the GTZ is no exception.  But for any valves to get banged up, your timing belt would have had to skip several teeth or break completely.  If you really want to be sure, you can manually set the engine to top dead center, and check to see if all the timing marks line up correctly.  You can also pull the heads and visually inspect the valves, but if the belt is in place, the timing marks line up, and the tensioner is working properly, your valves should be ok.
Good luck!