first let me say I am used to my 70 K-5 it is simple but I have a 94 S-10 4.3 W engine that was pulsing and had bad mileage I put a EGR valve on that did not fix it, so checked the fuel pressure regulator and found that it was leaking and also found a broken stud on rear of intake. Fixed that now it has a very high idle and then has an intermittent miss. Could this be the IAC I am out of ideas and it is the wife's truck so I am not getting any rest till it is fixed

 

If it didn't idle high before the work under the plenum, I would suspect a vacuum leak before an IAC problem.

 

Yeah I would go for the vaccum leak first. You can spray carb cleaner on all the hose connections while the engine is running and if the RPMs go up you found a source for a leak.

You might want to check the throttle linkage maybe the cable didnt fall into the groove and is holding it open a little too?

Did you clean up the junk out of the EGR ports too?

If its running like poop it should be giving you a check engine trouble code, jump the connectors and tell us what codes you are getting.

 

Thanks Guys for the help. Will look or the vac leak after work

 

If you vaccum line connections are loose or wobbly you can trim the hose end off and put it back on, some people like me also run a ziptie on real tight just to make sure kind of like a hose clamp. Pay special attention to your PCV valve Ive seen a million of them thats loose, it seems the rubber they make the grommet with doesnt like years of exposure to oil and they get fluffy and dont hold the parts in tight.