What can cause pinging in engine when warm?

Place a drain pan underneath the radiator. When the engine is cool, drain the cooling system from the radiator into the pan.

Place a car jack underneath the oil pain to support it. Also, to protect the engine parts, put a block of wood onto the jack.

Disconnect the negative battery cable and remove the engine mount and bracket on the right side.

Take out the drive belts as well as the idler pulley bracket, the chain tensioner cover and the water pump cover.

Push the timing chain tensioner sleeve up and put a stopper pin in it to keep it from slipping. Take out the chain tensioner assembly.

Turn the crankshaft pulley in a backward motion until it rotates 20 degrees.

Place 2 MB bolts into the threaded holes of the pump and tighten them by hand, alternating turning a half turn each at a time unit they reach the timing chain rear case. Doing it this way will prevent damage to the timing chain rear case.

Remove the water pump, throwing away the old o-rings. Make sure not to let the water pump hit the timing chair.

Clean all the mounting surfaces on the water pump and covers.

Install the new water pump with the new o-rings, tightening the bolts to 75 to 95 inch pounds (8.5 to 10.7 Nm).

Turn the crankshaft pulley back to its starting position (20 degrees forward).

Install the chain tensioner and water pump covers, tightening to .092 to 130 inch pounds (2.3 to 3.3 mm).

Take out the stopper pin from the timing chain tensioner.

Put a bead of liquid sealant onto the mating surfaces of the water pump and timing chain tensioner.

Install the timing chain tensioner with the water pump to the engine block, tightening the bolts to 87 to 113 inch pounds.

Add the drive belts, the idler pulley bracket and the engine mounting bracket with the engine mount.

Reinstall the negative battery cable and remove the jack from under the engine. Install drain plugs to the cylinder block.

Start the car and check for leaks when the engine reaches normal operating temperature.