Not sure if this goes here but I figured the motor forum has the most experience.

The motor is B18C1 with stock internals (except for ITR Cams), has 210,000 miles, and burns about a qt of oil a month. I just recently did a full tune up w/ timing belt and valve adjustment. The motor only knocks for about a second when I first start it cold in the morning. I'm guessing that its just a little piston slap, seeing that I'm also burning some oil.

What do you guys think it could be? Should I be using a thinner oil to help with cold starts, but will probably burn more oil. Or should I use a thicker oil to help it seal better? I live in cali so not really that cold here. Whats the thickest oil I can run? Is 20w-50 too thick?

 

Read your owners manual. What does it say?

 

having the same exact problem with my LSV... was thinking it was a rod knock the whole time but my motor still runs strong after it warms up

 

How long does your noise last? My noise last for only the first second when I start the engine.

 

Whats the thickest oil that you guys think would be good for a motor with over 200K?

 

Thick oil is a bandaid. Masks the sound. If anything get a thin oil to get to the parts faster.

Gm engines have cold start knock. Something like piston gap when cold. As it heats up the gap shrinks.

I am sure there are other possibilities others will bring to the table.