How do you diagnose an intake manifold leak? on 1996 Ford Explorer

Check engine light is on-Code P0174 says system too lean-left bank.

Asked by for the 1996 Ford Explorer
I like to use a smoke pump, which blows a thick smoke into the intake and the smoke will be visible where the leak is. It's however expensive, $ 1000,00+

Thanks much ZeeTech. It confirms the diagnosis.
hey zee - i still use the carb spray test and wish i could afford the smoke tester.
I use to do that too, but I have seen 2 car fire in a major chain shop near us because of the carb cleaner and that made me rethink my intake leak diagnostic strategy. :)
The big advantage of the smoke pump -beside the safety- is that you can really pinpoint the leak and it also works on the EVAP system. I was using it to find air suspension leaks too.
I have a Redline Smoke Pro and I love it.

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Great topic. You can do all kinds of great things with a smoke machine. Such as trying to find the source of pesky wind noises inside a car. Good stuff. Worth the investment.