To find out if your exhaust system is blocked, you can measure the exhaust back pressure with a back pressure gauge. Generally, when idling, exhaust back pressure should not exceed 1-1/4 PSI.

Palmer Wahl Instruments Inc. has introduced a new line of digital pressure test gauges that includes the Palmer 3PC Auto ... create a pressure range from 28 inches of mercury up to 6,000 psi.

Naughton said the pressure could even get to 8.0 psi if windchill is a major factor. “Ignoring the wind chill (meaning the following is a conservative estimate, meaning the wind chill could make ...