got my JDM b16 through autowerks in mi, and they said they compression and leakdown tested it for me. not trusting them, i took off the spark plug cover to see dirt and mud in there. kinda hard to do a compression check without taking the spark plugs out...

anyways i did it and i got this
#1 = 60psi
#2 = 5 psi
#3 = 190 psi
#4= 190 psi

he says all the jdm motors do that because theyve been sitting for so long and when the fire, they run rough, then smooth out and have good compresion. its kinda hard to trust something like this. he had another motor and he said it would do the same thing.

did this happen to anybody else before or did anybody get a jdm motor and it ran rough when it first started?

 

5psi?????

 

I dont think that your suppose to have any cylinders that low, let alone one at 5. Somthing is wrong. Bros engine came back with all four strong as can be and it was a b16a1.

 

If the engine has been sitting long enough in the open you might get these type's of numbers. Sometimes there is something keeping the valve open, like dirt or corrosion. The best way to check it would be to do a leak down test with the cams out and both the intake and exhaust manifold off. Check to see where the air is leaking from........for example, if the air is leaking from the number 2 cylinder find the valve that is letting the air out. When you find the valve that is leaking take a 17mm socket on a short extension and put it on top of the retainer. While the air is still pumping into the cylinder, tap the end of the extension with a hammer.....not to hard just a enough to make a loud pop.......then see if the percentage of air leaking changes......most of the time the air blows out whatever is keeping the valve open and it will be back to normal. Now if it is the piston rings then I would take the engine back for another one....if you don't want to take it back then I would rebuild it. Hope this helps out a little.

 

i also noticed that in that cylinder with 5psi, the intake runner is clean. The others are carboned. This would be a sign that it was misfiring when it was in the previous vehicle.

I took the engine back and told him to fix it or get me a new one.

 

i heard its completely normal to have anywhere from 60-200psi in any cylinder thats been sitting more than a few months. They fire and clean themselves out then you check it again and they are all at 180-190.