If you're looking at the min/max values displayed for the boost monitor on the Accessport, I would say that the pressure you're seeing is within spec. The Ford boost control system is highly adaptive to the conditions in which the vehicle is being operated, and will vary boost pressure to create a more regular, consistent engine output. Relevant factors are ambient temp., barometric pressure, intake air temperature, etc. Target boost pressure also varies primarily based on RPM, charge air temperature, and inferred fuel quality.
For your pinging issue - I'm personally hesitant to draw conclusions based on descriptions of engine sounds, but datalogs don't lie! Let's have you capture a datalog with your Accessport of engine operation where the pinging occurs on the Stage 1 91 OTS map. If there is knock occurring, the engine's knock sensors will report that data to the ECU, and the Accessport will be able to log it. Use the default datalogging list (already set-up, no need to change). Email that in to
[email protected], I'll check it out, and we'll move on from there!
For others referencing this thread now or in the future, one easy way to asses long-term knock activity and fuel quality is to look at the monitor Knock Octane Modifier (KOM). This is a global timing and load modifier that increases with high fuel quality (max = 1), and decreases with poor fuel quality (min = -1). This is the core of Ford's octane learning system, which remains in full use in our OTS maps. If significant and/or regular knock events occur, the ECU will decrease the KOM value. Through the use of KOM-based control tables, decreases in KOM will retard ignition timing and load targets globally across all engine operating conditions to accommodate for lower quality fuels. In general, all 91 and 93 octane OTS maps will run at a KOM of +1. HOWEVER, there are limits on KOM - namely, coolant temperature and RPM. At low or extremely high coolant temps, KOM will be limited to a value potentially lower than it's 'learned' value. This, by design, is a part of Ford's strategy for engine safety - limit power when warming up, limit power when overheating. So, if you want to check out what your truck is reporting for KOM, let it warm up to normal engine operating temperatures first.
If anyone has questions or concerns, please do not hesitate to reach out to us.
Thanks,
Sam@COBB