I own a 1989 MB 300SE. It starts up fine, runs for about 5 minutes, then dies.
It usually dies right after it warms up ( 80 degrees C) , while idling. It will not start again until the engine to cools down. The only problem that I know that I have is an exhaust leak. Someone said maybe there is an "Idle Sensor" that is not functioning. Any suggestions?
Thanks,
MK

Check the large vacuum hose right between the intake manifold and the valve cover. It's on the right hand side of the engine (if you're facing it from the front), about halfway back and on the top. It's a right angle hose, with two 45 degree bends in it.

This hose likes to get huge gaping cracks on the underside where you can't see them. Sometimes, they hold a seal well enough for the engine to run until it gets hot and the cracks open up. Then, the engine dies.

You can order that exact hose online, or Advance Auto sells an S shaped emissions hose that you can cut in half (in the HELP! aisle), and it works well.

Check that first. If it ain't the problem, please post back.


-J