I have a 2004 Chevy with a 5.3L that currently has 182k miles on it. Occasionally on start up it will have a fairly violent shake, aside from the shake it starts normal, and once started the engine runs smooth and quiet. When it does occur, it is usually after it sits for a period of time, like after a day at work. Could I have a fuel injector the is leaking causing the shake on start up? What is confusing to me is the randomness of when this startup shake happens.
Any advice on how I can start diagnosing this issue would be greatly appreciated.
Thanks in advance.
Mike
you could connect a pressure gauge to the fuel rail and do a leakdown test .
An injector balance test with a good diagnostic tool would find a leaky injector too.
did you find the cause of your coolant leak?
The only thing I was able to find was a small leak on the O-ring of the water neck/thermostat. Replaced it and it haven't had any issues since.
Mike