When shutting off ignition on my 05 blazer ls, makes the clunking noise you get when shutting off a diesel motor. Any suggestions?

 

Does it knock when its running? More, louder, in cold weather?

 

No it doesn't knock or anything. It just does the shake and clunk kind of sound like shutting down a diesel truck. I gave it a full tune up. Plugs, wires, cap, rotor and even cleaned the throttle body, intake valves and put in a feul system cleaner.

 

I assume your blazer is an automatic being as it is an '05, because if it is a manual it is just clutch chudder and if you turn the engine off with clutch engaged it should stop the sound.

If it is auto... I would venture to say you have fuel leaking from an injector and hitting a spot hot enough to ignite without spark. Fuel pressure test would be in order to diagnose that. Maybe a thorough injector cleaning will correct the issue without actually diagnosing.

Any codes being thrown? If the engine is running real rich that could cause it as well.

 

It is a manual. I tried shutting it down with the clutch engaged and no noise. So it is clutch chudder. How can you tell if its running rich or lean?

 

check engine light would be on otherwise you should be fine.