I'm slowly learning more about my truck, and am hoping to pinpoint the issue.
I spent the money on a hydraulic hose, and analog gauge to hook up to the heads. I also have access to the Auto Enginuity software. I was able to take a ride in my truck today to get some data. While I had the AE software going, I was also monitoring the gauge (100psi-4000psi). Here's a screen shot of the AE readings.
The truck has been having P1211 code problems (doesn't run bad after code is thrown). It will happen when going up a hill, or when flooring it around 3000rpms and 50mph. I tried 4 times today to get the code to throw, and it would not. All the high-speed passes are in red on the left. What has me perplexed is the steady cruising on the right. Take note to the area highlighted in blue. The IPR duty cycle is way high (notice it steadily climbs over a short time period, and the engine speed and pressure seems to remain constant. Once it peaks out at 50% for 4 seconds, it drops to normal.
The truck has a new ICP, HPOP. It supposedly has a new IPR, but it looks like its been on there for a while. Could this be an electrical problem?
The truck does run rough for a few seconds if you shut it off, and restart it while it is hot. If I unplug the ICP, it does not do this.