It is miss firing and the garge i took it to told me that the injectores are wore it is very hard start in the morning if it starts lot of smoke comes out first than it has got shaking on engine and cluch padal my car is audi a6 tdi 2001

I assume it will still spin over but just not start.
Do you get smoke at tailpipe while cranking it over?
If no smoke, then it means the injectors aren't firing.
Typically, there are three reasons why injectors won't fire.

1. Low voltage while cranking (Check battery for proper voltage). Check all connections, especially at Starter. Starters get funky when hot and may not spin fast enough (See #3).
2. Injector control pressure below 500 psi (HPOP oil)
3. RPM not fast enough while cranking (CPS)

Water in the fuel would cause issues when cold and hot. Have you checked the fuel bowl and found water?

Since you mention an injector miss already, then I would start there and confirm items 1 through 3 above.
Wa

normally it will be hard to start or will not start ---there may be missing in the engine ---there may be loss of power --the rpm's may fluctuate widely --- it may blow lots of black smoke --- the motor may be over heating more---

at times miss firing on one cylinder is caused by the valve

dear . this problem of injectors when low RPM . you can loose pipe of injector while engine idle speed to check which injector .

Check the battery cables. I had the same issues with my 96 tacoma, The battery cable connection at the battery can be cranked down but still be loose. Hard to explain, doesn't make sense, but just check it out.

is check engine light on this could be a coolant temp sensor issue it could be a fuel psi regulator problem or bad injector or cold start injector if your vehicle is equiped if a diesel bad injectors or injection pump the black smoke is raw fuel

the spider legs in the intake mainfold at the top of the engine are leaking very bady. mine did the same thing and my mechanic took it apart and 4 out of the 6 injector legs were rotted and just spraying excess fuel into the manfild. the four that was bad was all nice and clean from the gas. the other two looked a little dirty like it was supposed to be.

jlwhelen,
I will suggest that perhaps the blue smoke is not purely oil. It sounds like you may have an ignition problem where the engine has a hard time firing until warmed. The blue smoke may be, at least in part, unspent fuel. I realize that a warm engine that uses oil will smoke blue, but excessively rich conditions on startup can result in a similar effect. If the choke circuit is delivering a little extra fuel from a dirty injector, the problem may be worse when starting from cold.
To remedy this, I would suggest a simple replacement of plugs and wires, as well as a fuel injector cleaner through the tank. I would bet money that these simple maintenance points would solve your problem.

Good luck!
Lucky

Check the power to the cold start injector. (it's only going to have fire for a few sec. after the key is turned on). If the fire is good, replace the cold start injector. This injector is activated for a few seconds when the engen temp is low to add a little fuel lower down in the intake and closer to the pistons.