Your engine knocks when you cold start it because the motor oil is not viscous enough to lubricate crank bearings, cylinders, etc. warm it up first, engine will last alot longer
Worn main bearings sometimes knock when cold starting
Some cars will knock for th first minute or so on a cold start until the oil starts to circulate through the engine
Often a knock when cold is caused by piston slap, which is pistons rocking in the cylinders until they expand in size when the engine warms up.
Make SURE the engine is COLD. Then unscrew the old sensor and install the new one. Antifreeze will leak out of the engine so be quit when replacing it.
it is just a characteristic of the truck with the 5.7 it is normal kind of annoying though
This is a common problem when cold on these Chevy engines. As long as the motor comes out of it as it reaches operating temperature, I would not throw dollar bills at it.
It could be that the timing is off. You may need to retard it.
Cold engine knock that goes away after warmup is usually piston slap. Worn pistons worn cylinder bores, wrong oil (too light) on a high mileage engine.
This is a electronic fuel enjected engine and therefore the electonics set the engine idle speed a bit higher during a cold start so the engine will not stall out.
I need to know why do i need to crank my chevy truck to start ?
because the engine is cold and you need to keep the engine warm.
One is the Head Temp sensor, other is either a knock sensor, or on the throttle body it's the cold start injector