checking for vacuum leaks

[jcwaters1]

hey, im suspecting a vacuum leak is the reason for my rough idling. it only does it after the battery has been disconnected, and the check engine light has been coming on and going off intermittanly. i had the code read and they said it was an O2 sensor, but i have heard that its usually a vacuum leak instead. i am planning to check it, but i was wondering where exactly to hook up the vacuum guage. its the 4.0 SOHC. i have the repair manual for the explorer, but it doesnt say EXACTLy where to hook it up. it just says the intake manifold vacuum.

thanks

 

[jcwaters1]

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[jcwaters1]

oops sorry, i meant to say, what kind of gauge should i get? hit the button too fast

 

[2000StreetRod]

Vacuum gauge

I'm not aware of a way to find a vacuum leak with a vacuum gauge. The intake manifold gaskets on the SOHC are prone to drying out and shrinking with age which results in a leak. The leaking is usually worst at cold start and the colder the start the worse the leak. The leak results in air entering the engine that has not been measured by the MAF sensor. The PCM relies on the MAF sensor to determine how much fuel is required. Intake leaks result in a lean engine condition. I suggest that you perform my "Lean condition procedure". Click on "My Helpful Threads" in my signature for a link to the procedure

 

[Paraphoe]

I would think if you had a leak your engine would be throwing lean codes with the O2 code..