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Does it feel like it's running well, or does it feel like it's missing?
What we have seen a lot of is injectors leaking because of ethanol deposits causing them to stick slightly open. This runs the fuel mix a little richer and drops fuel mileage (but the truck will run pretty good.) A quick way to check it is measure fuel pressure as the truck is shut off. If it loses pressure at the rail quickly then it usually means the injectors are not fully sealing. It is also possible to see evidence of it on a scanner that would show fuel trims to be very low (the computer trying to compensate for the extra fuel).
I think the Genesys might, I don't know about the Snap On. Look in parameters for fuel trims, long and short term.
It looks like your B1S1 sensor is kinda weak. that 12% fuel trim may be due to that. You really want to be consistently under 10, but 12 is still probably not going to set an O2 sensor code. There really is no smoking gun there, but if the trim didn't comedown with a new O2 I would start to think an injector may be clogged a little.
Well, remember that you are looking at computer generated data read by a scanner and not the actual voltage from the sensors, so it will not show a true switching pattern. The downstream sensors have no effect on performance so you don't really need to change them, and they normally run much lower and slower switching than the fronts. That being said, the computer uses the difference between back and front to monitor the cats, so when you change the fronts you may start to get a P0420 code because of the weak rears, then you'll need to change the rears also. In order to really see the voltages on O2 sensors you have to put them on a scope, but your numbers are somewhat suspect and O2's don't cost a lot.
To analyse the cats properly with the O2's you have to use a scope, most scanners will not give you a good pattern. You could do a vacuum test to see if you have any backpressure in the exhaust , but unless they are really clogged I don't think you'll see anything, and it runs well. If this is a customer's car replace the O2's and warn that they may show up a cat problem. If it's yours do it in phases, fronts, rears, and finally cats if a 420 shows up and won't go away. I have seen a lot of older trucks do that after new O2's so always warn about it if it's a cust car.
Yup, sounds like it may be that #1 injector sticking. ST fuel trim should probably be negative too, correct?
If the connector was bad it would run lean, sounds like you are rich.
Looks like the coil could be the issue. See if your scanner will read Mode 6 and look for the 50 series counters. These are misfires. 51 will be high because of that code but you may also see some others. Those coils ate suspect too.
Absolutely. But early on you daid you replaced the coils.
Yeah, there is a lot of Chinese junk out there. At one point you couldn't even find those coils so everybody started making them, and some are pretty bad. If you can get that Mode 6 data, it might show other coils that are weak too.
May not have been real, lots of clone stuff out there, it's kinda crazy.
Ford only shows misfires in Mode 6 until the counts get very high. Does your Snap on tool show Mode 6 info?
Cool, let me know.