Few cars today need the "high test", premium, supreme's anti-knock composition, our engine computers are smarter, adjust for combustion issues..
I just went through, over the last few months a bit of an education on my F150.. I had some bad coils, causing misfores, but only at certain rpm/spped/load... My mech is great at sharing, showing, discussing the things going on.. No codes were setting, so we had to trick the system a bit to force the misfire on the road, save it when we stopped, in one case disconnecting the brake switch so I could ride the brakes a bit to cause the misfires.. If the brakes are on, they aren't recorded, normally.. So a couple times we pinned it to a couple, but after 4 were swapped, it was still misfiring, rather than tie him up again, I ordered, replaced the remaining 4 coils (COPs), and it appears to have cleared it.. I never knew before this that the computer hits with 3 strikes, at an idle, and from the waveshape he can till if it was lean or rich at that instant. It is not the simple condenser/points/coil from days of old.. There's a lot of info out there, some tucked in dealer training, other in class materials... We take a LOT for granted, every second we drive...
weco
- -