i have two codes. mass air flow and cam shaft position sensor.i replaced both of those also the wires,plugs,cap and rotor. i also have a knock.what the heck could this be.i am mechanically inclined also.

 

Welcome to the Tahoe forum. Did the new MAF and cam posit. sensor fix the original problem?

 

no i guess it wasnt the problem the whole time.the engine has a knock when it gets warmed up.always has.it just sucks because i bought this thing thinking that it was nothing serious.come to find out im probably gonna have to swap the motor.

 

double check the firing sequence, make sure all the plug wires are going to the right plugs, make sure the wires are in seperators and are not cross firing.

On the passenger side of the engine at the front near the altanator there is a wire bundle that passes very near the engine block, check it for any burn thru or melting, this harness carries the crank shaft position sensor.

The cam shaft positon sensor comes right out of the distributor, check the harness there also, make sure no harnesses lay across the coil wire and that all spark plug wires are above any wiring harnesses.

Use heat shilding tape to rewrap.