Fixing air leaks with a 12 valve fuel heater delete

If you're tired of your old Dodge hunting for idle or stalling out at stoplights, doing a 12 valve fuel heater delete might be the smartest afternoon project you can tackle. It's one of those "while you're in there" jobs that saves a ton of headache down the road, especially if you're chasing a mysterious air leak that's making your truck run like a bag of hammers. The 12-valve Cummins is legendary for its reliability, but the fuel system components bolted to the side of the block haven't always aged as gracefully as the engine itself. ...

February 13, 2026 · 6 min · Sahle Nathaniel