siboost93

hey if anyone can help that would be great, i have a 93 si with a boosted stock z6 i started to hear a tapping noise from the head i popped the valve cover adjusted the valve springs and it didnt go away so i took the head off and noticed that the edge of the piston closest to the cam gear(not sure if thats 1 or 4) is hitting the the flat edge around the combustion chamber. i dont have a rod knock or anything like that just the slight tapping, another side not is the car had a hard time idling, if i cam to a red light it would stall, i obviously have to rip it all apart but i just want to know if anyone has had the same prob and wut it might be, can the rod stretch? could the crank be the prob? idk again any help would be great!

Luserkid

Take pictures of the head and block. Its VERY rear to hear that the piston hit the head on a stock motor. Only way i could see that happening is if you have a major rod failer.

siboost93

yeah thats wut i thought i will try to get my hands on a camera, but if i had a major rod failure would the car still run and drive? it still ran i mean even hto i heard the tapping i had to take it out one day for something i forgot but anyway i wound up runnin this kid in a ser sentra it still pulled on him hard just when i came to a stop the engine wouldnt stay idling it would shut off and to start it again i would have to give it gas as i cranked it! i haved had rod failures in the past and they usually sound like theres a midget in there with a jackhammer! this is more like a midget with a dinner bell!

Luserkid

Picture and check your rod bearings.

Mr.Kalinchuk

Its your rod bearing.. obviously if its a stock engine and only one piston is doing it. Rods don't stretch longer so take that out of your possibilities. Take your bearing cap off and look at your bearing.