Used to hate electronic injectors till I saw a buddy's data log

I was always old school mechanical pump guy, thought all this electronic stuff was just more crap to break. Then my buddy showed me a scan from his laptop on a 6.7 Powerstroke that had a dead miss. He pulled up the cylinder contribution test and saw #4 was at like 80% below the others. 20 minutes later he had a new injector in and the truck ran perfect. That data made me realize I was just being stubborn. Anyone else change their mind about something after seeing actual numbers?

3 comments

3 Comments

johnson.jesse8d ago

@skyler_smith85 is right about those numbers being funky but the point still holds.

skyler_smith858d ago

The cylinder contribution test is a good tool but that 80% number doesn't quite work like you're thinking. That test shows contribution relative to the other cylinders, not a direct percentage of power output. If #4 showed 80% below the others, that would mean it was basically making almost zero power while the others were carrying the load. More likely it was reading something like 20-30% of the average contribution, which is still a dead miss but the numbers get exaggerated in those scans. Either way the point stands that being able to pinpoint which injector is bad without tearing everything apart is a game changer.

williamhill8d ago

Hold on, is a dead miss really that hard to figure out? A good old-fashioned power balance test snap-on style with a tach and a couple of screwdrivers has been working just fine for decades, hasn't it?