compression test when block is cold or warm?

[drewdude92]

Should i do a compression test on my truck when it is cold? Or should i warm the truck up as much as i can with still being able to pull the plugs?

[67ZL1]

You'll get more acurate results when the engine is @ or near operating temp.

[drewdude92]

okie doke thats what i needed to know thanks alot i love this site!

[68gmsee]

I've always done my tests with the engine warm, but not hot, to keep from burning my fingers.

Depending on how bad it is and how accurate a reading you want, I'd just run it for a few seconds (seconds), until oil gets up into the walls and then test it. Then, if you're still are not sure and want a more accurate reading, run it and turn it off before that sucker gets too hot and do it again...

But, be careful, those spark plugs get hot pretty quick! Don't ask how I know these things...

[drewdude92]

haha yeah i tried to change plugs one time when the engine was hot...ended up with a nice burn on my arm from the headers...