My car has a hard time starting any time of the day, even in 90 degree weather, not only on cold mornings(because I know diesel engines have a hard time starting in cold weather). Is this some sort of vacum problem ? Also when I turn off the ignition, the engine shudders and moves side to side like it's not held in place really well.

Bad motor mounts can cause the engine to "shudder" when you turn it off. As for hard starting hot or cold, that can be a number of things. You can start by checking the valve clearance(cold engine);Check the dampening screw on the rear of the injection pump.Make sure it is not screwed all the way in;Check fuel pump to make sure it is delivering enough fuel at cranking speed. Last but by no means the last reason your engine is hard to start, is do a compression test on each cylinder.For non turbo engines the normal pressure is 22-24 atmospheres(hot engine)Minimum pres.about 15atmos.
Max. difference between any two cylinders is 15atmo.For turbo engines the normal comp.pressure is 24-30atmo. I believe one atmos.equals about 14.7psi.
Good luck with your starting problem
Bill Lewallen Lexington,Ky.

Correction! Permissible difference of pressure between individual cylinders is 3atmos,not 15. Bill L.

First, make sure that your in-tank filter, pre-filter, and fuel filters are okay.

If filters are goos, go to a Bosch diesel fuel injection service shop, and ask them to try increasing the "no air" fuel delivery. This adjustment can be done in 5 to 10 minutes without removing the injection pump.


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Jake