Hello,

I have a jdm b16 with a built head on it the car still ran strong but for some reason it smells like fuel real bad and gets bad gas mileage, pulled off the 1-3 spark plug wires, 1 at a time and the motor sounded like it was gonna die out( normal) now when I pulled off the #4 cylinder plug wire it didn't do anything motor stayed idleing the same.

Now keep in mind this car didn't even smoke or knock, and maybe lost a quart of oil in a 3k oil change

Did compression test on the #4 cylinder and it read 50 PSI
#1 cylinder read 225 PSI

Tore the head off the block and looked at the cylinders and the walls look perfectly fine. Not one scratch or blemish in the cylinder walls

Anybody have any idea why the compression is so low

 

dont pull your spark plug wires while the car is running. What did your spark plugs look like? What were the other compression test numbers? And did you do a wet test?

 

Spark plugs looked fine. And the others read 225 also. And no did not do a wet test.

 

What do you mean looked fine? Do you know how to read spark plugs?

 

Had a brownish white tip.

 

Perform a leakdown test. It will tell you exactly what the problem is.

 

He said the motors already torn apart

 

Missed that. I don't see where he inspected the head itself.

 

I don't see anywhere where he inspected anything but the cylinder walls.

Op have you pulled the pistons from the block?

 

hello i have a b18c block on a b16a head my question is i pulled out my spark plugs and they seem to smell like gas which they did not before my car seems a little weaker than before..i wanna know what i can do can anyone help?

 

Sounds like the valve lash on #1 cylinders exhaust valve(s) it too tight and an exhaust valve is staying open a little, = low compression, engine runs like crap, stinks of gas, gas mileage is bad.

It also sounds like you have more then one problem, if there is no diff. in the engine rpm when you pull a spark plug lead, [#4] that cylinder is not firing, possibly no spark or no fuel, even low compression.

This assumes the compression test was done properly and the compression tester was working properly.

grumblemarc is correct, a leak down test should have been done before the head was pulled, it would have pointed you in the right direction.

All you can really do now is either put it back together again, do a valve lash adjustment and test it again, if there is still a problem, [low compression] on any cylinder do the leak down test.

With that said, now that the head is pulled, it may be worth replacing anything that is at the end of it's life, maybe a valve job, new guides/seals, how about the piston rings, how many miles on them? 94

 

Sounds like the valve lash on #1 cylinders exhaust valve(s) it too tight and an exhaust valve is staying open a little, = low compression, engine runs like crap, stinks of gas, gas mileage is bad.

It also sounds like you have more then one problem, if there is no diff. in the engine rpm when you pull a spark plug lead, [#4] that cylinder is not firing, possibly no spark or no fuel, even low compression.

This assumes the compression test was done properly and the compression tester was working properly.

grumblemarc is correct, a leak down test should have been done before the head was pulled, it would have pointed you in the right direction.

All you can really do now is either put it back together again, do a valve lash adjustment and test it again, if there is still a problem, [low compression] on any cylinder do the leak down test.

Or, with that said, now that the head is pulled, it may be worth replacing anything that is at the end of it's life, maybe a valve job, new guides/seals, how about the piston rings, how many miles on them? 94