My old shop foreman swore by a $12 infrared thermometer for finding vacuum leaks, and I finally caved
We were chasing a rough idle on a 2011 Silverado for two hours with carb cleaner last week and got nowhere, then he grabbed the IR gun and found a leaking intake gasket in about 90 seconds. I've been doing it the old way for 8 years and now I feel dumb, but I want to know if you guys use temp readings for anything else. What other jobs do you reach for the IR gun on?
The IR gun trick works for vacuum leaks but I would not lean on it as a first step, because you can burn a lot of time chasing normal heat on a cold motor. Carb cleaner still tells you faster on most intakes, and you get an instant change in idle instead of guessing at temps. The real value of the IR gun is exhaust work, checking cats and headers for a dead cylinder, and that is where I keep mine.