Need help with boost problem

[Gsf1200m]

I went Unitronic stage 2 about three weeks ago and had the cam, hpfp, and cam follower replaced. The shop told me that the lpfp was about to go but I didn't have it replaced at that time. Over the weekend of 12/12 the car would only boost to 4psi for a couple minutes and then when I was still driving it would go right back to normal. There was no CEL and everything felt normal before, during, and after this happened. The next week I had the lpfp replaced thinking this was the problem. Everything has been fine until today, going to work the same thing happened again, and then once again on the way home. No CEL, everything felt normal, and the car went back to normal after a few minutes. It has the new style diverter valve, and I just used MAF cleaner on the MAF. Anybody have any ideas for me?

[Gsf1200m]

Shop wants to replace the high pressure fuel rail sensor and the fuel filter. Unless the problem starts getting worse I will wait to get those things done, I had a very large bill from the cam follower stuff and tune.

[Sanjman]

Shop wants to replace the high pressure fuel rail sensor and the fuel filter. Unless the problem starts getting worse I will wait to get those things done, I had a very large bill from the cam follower stuff and tune.

Seriously fuel filter is so easy. So it yourself. If you got a new lpfp why wouldn't you get a new filter?? Trying to kill your new pump quicker?

[Gsf1200m]

I don't know why he didn't replace the fuel filter at the same time.

[Gsf1200m]

Still need help. The car is at the shop right now and he hasn't been able to reproduce the issue, and there is no CEL so he is not sure what is going on. Seems like the car was going in and out of limp mode for me while I was driving. I have a new fuel filter that I am putting in when I get it back. I am taking it back Saturday either way, but it seems like it will still have issues. I am considering going back to stock on the tune but I don't know if that will do anything. I didn't have this issue until after the tune. If anybody has any ideas for me to check out when I get it back I could use the help.