Smoke test

[kiboko]

I performed a smoke test on my 1997 Ranger 4.0 OHV today. Cheap homemade smoker worked just fine. And here's my question: the IAC leaked like a sieve. It did not leak at the gasket, a bit at the vent but the crimp joint in the body of the IAC motor produced copious amounts of smoke. I have a spare; tired it and it leaked too at the same place.

Is this normal?

It seems to me that this leak could allow un-metered air into the system and may be a potential cause of p0171, p0174, which I have been trying to eliminate for months.

Both of my IAC valves are aftermarket. I wish I had a Motorcraft to check.

Any input appreciated.

 

[snoranger]

OEM will leak less then aftermarket. I've seen some that will leak a little from the seam. Silicone it up, let it cure overnight, and see if that solves your problem.