My old 7.3 Powerstroke went from 14 to 19 mpg after I finally fixed a boost leak

For about six months, my truck felt sluggish and the fuel gauge dropped way too fast. I kept checking the usual stuff, injectors and fuel pressure, and it all seemed okay. Last weekend, I finally got around to pressure testing the intake system and found a tiny crack in the intercooler boot I couldn't even see. Replaced that one $45 boot, and the next tank of fuel I got nearly 5 more miles per gallon. It's crazy how one small leak can waste so much fuel. Anyone else had a simple fix that made a huge difference in fuel economy?

3 comments

3 Comments

henry6041mo agoMost Upvoted

That's just a fluke, your driving habits probably changed.

julia_carter701mo ago

Have you ever had a car that just felt different after a fix? My mileage jumped a solid three miles per gallon after that tune up, and my routine is the same old commute. It made me realize sometimes a simple repair can have a bigger effect than we expect. I really don't believe it was just my driving.

phoenix_carter1mo ago

Honestly, I used to be like Henry and just chalk it up to luck. But last year my old truck was running rough. Got the spark plugs swapped, which seemed minor. Suddenly it stopped that weird hesitation pulling onto the highway. It wasn't just a feeling, the engine noise smoothed right out. That kind of thing makes you a believer.