Chasing gremlins on a 01 Ford 5.4L looking to see anyone here can help. Unless there is a specific forum or scanner diagnosis forum I should go to.
NO CODES!!! Maybe just wait until the trigger a code.



No CEL, CAT Incomplete for weeks

No CEL, EVAP Incomplete for weeks

On top of that I got this as well...

This has yet to change.

I did have this at one point but it went away.

This goes from ok one day to fail the next. I'm thinking maybe the Knock Sensor?

At Idle and acceleration to 60 - 65 mph both SHRTFTB1S1 and SHRTFTB2S1 show fluctuating readings, SHRTFTB1S2 shows zero continuously, and SHRTFTB2S2 stays fixed at 99.2. These were this prior to exhaust repairs.

The LONGFTB1 and LONGFTB2 both read 0.00 and rarely change.

O2 readings are all under 0.80

Rough start on the morning of 5/17

Recorded Fuel Trims that morning not sure if this is the correct way to do this.

I got 315 freeze frames in a 20 minute ride.

The Shorts got no lower than 20 and no higher than 26.9

The Longs never changed once and stayed at 00.0 the entire time.

Let me know if I did this wrong or if it was not even necessary.

Maybe I need a smoke machine? Any suggestions without the use of and air compressor? I see Amazon has a few AUTOOL units for sale with built in air. I question the pressure on their SDT 106 unit. It has an output of 9-11 psi. I thought I read somewhere that an EVAP test should not exceed 1 psi. I questioned the seller and they replied with "9-11psi is the pressure range that the automobile pipeline can bear. If the pressure is too small, the leakage detection will not be carried out. I hope it will help you." Does this make sense?

Any help is appreciated. Thanks in advance.

 

Seems like your truck is stuck in open loop. Those STFT should drive the LTFT up. Usually cel will not come on with a code if LTFT is around 0. Possible engine not getting up to temperature or o2 fault may keep truck in open loop. Good luck with that one .