Weak power steering on my '97 sometimes

[scotts90ranger]

sometimes the power steering is weak on my '97 (extended cab 4x2), IE hard to steer in parking lots when you're slowing down and the engine is at idle (mainly when it decides to idle at like 500rpm, maybe I should clean the IAC...). If you blip the gas it steers fine with more pressure. I checked the fluid level and it's fine, so does that mean the pump is going out? Would I gain anything by draining the fluid, cleaning the check valve on the side fitting and refilling with new?

Just trying to narrow things down, the dumb thing doesn't make any noise or leak which is nice, but power steering is kinda useless when it doesn't help you steer...

 

[Shran]

Weak pump would be my guess but didn't the 4 cylinder trucks have a pressure switch on one of the hoses to compensate for this issue at idle?

My Explorer did this, specifically when cold. I replaced the pump with the Jeep one and the problem went away so I guess in my case it was the pump at fault.

 

[scotts90ranger]

I don't remember if this one has a switch, I know the '90 does...

I'm leaning toward weak pump, it's not just when the idle is low, pulled into another parking lot tonight and the idle was like 1000 and it was a bit hard to steer, little bump of throttle helped... at around 200k miles I think it might be the stock pump so it doesn't owe me anything...