Benched pump issues

Alright guys I'm having some issues with my pump and before I pull it and send it to a shop I figured I'd see if anyone had any input.
I'm running a benched 215 pump with comp cuts and 5ks. I was in the process of trying to tune the afc due to going to a 366 top charger and 5x.018s. I slide the afc back to try and cut fueling back down low. When I started the truck and tapped the throttle the rpms shot up to around 2-2200 and dropped down super slow. After tapping it a second time the rpms stayed up around 2k and seemed as though they were rising. I slide the housing back to being full forward and it run fine. So I left it like this awhile with no issues and ended up swapping in 7mm dvs and I loosened up the star wheel to start tuning it again and it started doing the same thing. I pulled both sets of springs out of the pump to check for and issues/ any shims still in it and found nothing, both sets of springs were adjusted correctly also. I reset them and still had the same issue but the rpms weren't shooting up as high instead they were hanging around 1100 and falling back down very slowly. I backed each set of springs off 1 click and it seemed to fix it. After running it a couple times I noticed it was still doing it but not as bad it'll hang around 900-1000 and fall slower then normal. Any input would be appreciated. I just wanna see if there's anything I over looked and didn't try before I send it to a pump shop and spend a bunch of money.
Thanks !

I also have a benched 215 in mine. Have had weird issues.. like if I raise the idle too much, it will hang randomly and spook the heck out of me. Worried its about to run away on me.
I would check your idle setting also. With mine, just a small amount was enough to stop the problem.

It's not the idle adjusting it didn't change the situation

Nobody else has any input on this??

Do you have another set of idle springs you could try?

No, what doesn't make sense is why it changed so derastically by sliding the housing back.

Mine also will rpm hang with a benched 215 pump if idle is set to high... good luck.

Hmmm.. if its not idle Im not sure what else it could be. The afc does nothing but restrict travel till boost lets it move out of the way.
Have you readjusted the governor arm contact point since the plate was installed, or verified its in the right spot? And that the arm moves smoothly?
It doesnt sound like its hanging under it at all, but thats the only thing the AFC was doing before being moved.

I'm not running a plate but the odd thing was when I had the arm in the afc the throttle would go enough to let it rev till 1k then it would stop solid till boost came up. I get the fact that the arm limits rack travel but I guess it's possible for the governor arm to be below the foot causing it to stop completely till boost is made?

Correct the arm should climb in my experience.

That would explain why the pedal completely stops till it makes boost. What's the correct why to adjust it? I'm sending my injectors out tomorrow to have them checked also before I go sending the pump out.

http://dieseldatabase.com/turning-up-a-p7100-pump/
at the bottom it explains how to adjust the arm.
who benched your pump originally?

hope that governor adjustment is the problem. Sounds unusual for it though, unless I read the first post wrong.
Good info on the benched 215 idle hang. I thought it was just my pump doing it.

I double checked everything and ended up having to drop my idle down to 500 to get it to stop. After I drove it and got back to my shop it tried to stall out on me even though it was idling fine it would just start to die down. I switched my comp cuts back in and played with the idle and she's running great now. My only issue left it the governor arm is sitting under the afc arm and causing it to hang till it builds boost so I still have to get that figured out.

I've been doing a lot of learning with my AFC lately and found that if using the stock spring and the star wheel adjusted full forward ( applying no load on the spring) it allows about a 1/4 inch of slop between the spring and the diaphragm washer which means there is nothing pushing the AFC foot back to idle. Might be what is causing your problem. I'm in the process of finding a spring that is longer but has less coil to avoid the coil bind which will limit full fueling. Let's us know your results!

this has also happened with me mines a maxed out 180 pump same issue though it comes and goes and sometimes it feels like its hard to push peddle