[Bigtex93]

Originally Posted by danielsatur

A smoke test is usually done at a shop, they blow smoke through the Air box, duct work, intake, EGR, and PCV systems to find air leaks.

Any unmeterd air leaks will confuse your ECU/PCU, the Air/fuel mix will be calculated wrong, thus lean codes will be thrown.


A backyard Tech, or mechanic will use brake cleaner, or starting fluid, while the engine is running. The rise in RPM's tells you that there's an air leak.
The EGR + PCV systems are the most probable cause, because of rubber, plastic, and seals leaking air.

The Positive crankcase ventilation (PCV) consist of a PCV valve, and tubing going from the valve cover to the air duct work on throttle body.

COST ?
I heard of a dude being charged $3.5k for a problem that wasn't fixed, it was a bad fuel filter.

Thanks for the tip....pcv valve extemely dirty..changed out..don't know if this will help

also sprayed Carb cleaner around intake, no increase in RPM...any suggestions on other places to spray? Thanks