Hi there, I'm looking at buying a used 1996 4runner (3400 engine)... and I plan to take it to a mechanic I trust. I've asked him to do a compression test on it just to cover my ass, but I really don't know what sort of compression numbers are typical for this engine. Anyone able to give me a hand with this?

 

I do not know the exact numbers but I do know that consistantcy between the 4/6 cylinders are important. (all around the same number)

 

You should see numbers between 150-190 psi (it will vary depending on mileage and a number of other factors) and all of the cylinders should be within 10% of each other. Ideally the test will show about 180-185 psi average and all cylinders within less than 5% of one another.

 

Well, I went and did it. Pretty much 165-170 all the way around.

I guess this means I'm moving on up to the '96-'02 4runner forum.

 

Nice, welcome aboard!