95 E420 running issues
 

This car starts and works perfect until it warms up then it bucks and misses and will not take the throttle. new wires plugs , I am wondering if it may be the crank sensor, and when it gets hot it may have a crack in it which does not give the proper signal , anyone ever had this type of issue

Typically when a crank sensor fails the engine shuts off and the one I saw was temperature related - it did it after the engine got up to temp.

So many things could be involved. How many miles on the M119? any codes? Not sure if the 95 model has dist caps and rotors or electronic coils. worn dist caps and rotors are a common wear item if your motor is so equipped. MAS can cause you fits too. Check for vacuum leaks around the intake manifold. with engine at idle spray some brake cleaner or carb cleaner around the intake manifold, targeting the rubber spacer/gaskets between the 2 piece manifold. The engine will stumble and possibly die if you have a leak. If they are sealed up tight, the engine will not stumble when you spray. check the #1 cyl area first.. that's where the EGR port is. It's very close to the #1 cyl manifold and it takes a beating from the exhaust gas and heat entering the manifold. The gasket can crack and cause all kinds of crazy problems....

If it's your intake manifold ring seals, brace yourself... about $300-$500 in various gaskets and seals and 20+ hours of labor. I rebuilt mine myself. Replaced every vacuum hose, gasket, ring, seal and hose I could access while the top of the motor was exposed. (rebuilt fuel injectors while I was at it). 100% corrected my crazy 400E.

Just a few ideas based on personal experience. Good luck!!!

this car has coils packs but I will try your intake leak detection advice thanks