throttle surge

[Fossilfreefuel]

I've seen past posts on this but never with what the cure was...

98 Suburban. Occasionally the throttle would accelerate out of control for a moment. Now everytime you turn it on it revs up just under the red line and drops and almost dies and then revs and black smoke pours out. The last post I saw indicated this is a PMD issue where the driver loses control of fuel metering. Any other opinions?

[JohnC]

It could also be a sticky fuel solenoid. Either way, the fuel solenoid is misbehaving.

[Fossilfreefuel]

does sticky solenoid mean new IP? I'm going to swap PMD's soon so that will be the first test. I already pulled the optical sensor to make sure it didn't have to do with that.

[JohnC]

Try running a heavy dose of fuel conditioner to see if it improves. Otherwise, it is not a user replaceable part.