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Hello
I have had a Rostock max v2 for awhile but it has always had the problem of the hotels hovering about 5 degrees below the set temperature. Then if the fan is on the temperature is about 15 degrees below what I set it too. I run abs at 235 degrees and have done multiple m303 commands to try and fix it

This can be caused by a couple of things.
The most common one is bad PID settings (and yes autotune can result in bad settings), if this is the issue you can get a higher temperature (all be it short of the target) by setting the target temperature higher. If this is the issue, you can resolve it by manually changing the I and D values to be lower, and possibly the P value to be higher.

The second issue is it simply won't go above a specific temperature, if this is the case it's either the PIDMax value in the firmware being to low (the range is 0-255), or you have either bad wiring to the hotend or a damaged resistor in the hotend. You can verify it's one of these by reading the resistance of the hotend circuit after disconnecting it from the RAMBO, it should be about 3 Ohms. If it's closer to 6 or more you have a problem with the physical wiring.

I will try this tommorrow

How did changing those PID settings work for you? I have been encountering the same issues lately.

I had set mine to 228. The first print would reach it to start printing, then it would hover around 225, and eventually down as low as 218.
MatterHacker guy said to try it (I had redone the calibrations dozens of times) without the PEEK fan turned on--I tried it and the hot end performed beautifully (I only have been printing with ABS).
I removed the fan and shroud entirely.