While iv'e been working on the rust issues I've let the mechanical parts that were on order accumulate.

Choke Pulloff
EGR
Heat Riser
Air Diverter Valve

All installed except the Heat Riser at this point.

So today I installed the new EGR valve and now it keeps creeping back up to high idle. Sometimes I can kick it right back down and it'll stay other times not. Just driving around a bit and when I stop it wants to stay at high idle. The electrical connection to the electric choke is suspect.

Not knowing how long the EGR has been bad I wonder if the carb was tuned to the faulty EGR. It is currently set pretty lean.

Currently timing is set to 12 degrees BTDC and it should only be 6.

The carb is due for a rebuild anyway and I'm going to replace the PCV valve and grommet, but what else should I be looking at?

 

I would start with the carb rebuild and work from there. Are the linkages tight on the passenger side of the carb?

 

There's slop just about everywhere in the linkages, hence the need for the carb rebuild. Plus the thing is absolutely filthy. The connector on the wire to the choke is split and very loose.

Had to put this issue back to the back burner as I need to get the sheet metal closed up. My company truck goes to the shop for a front differential replacement and address the check air bag light issue so ready or not the blazer becomes the daily driver for a few days. Luckily work is less than 2 miles away.