ok, cleaned IAC with TB cleaner(it was NASTY) , changed vacume lines going to DPFE(also NASTY-almost completely blocked with disintegrated line), changed plugs & wires(scary, cant believe truck was running at all) now truck wont idle at all. fires up, will run (sounds good!) if foot on gas pedal but if you take foot off pedal idle drops to nothing & dies. the EGR Vacuum Regulator makes hissing noise for a minute or so after truck dies but no codes are being thrown. was throwing EGR code(also misfire #4 & #7) to begin with(insufficient air flow) fixed by changing lines to/from DPFE, then idle started dropping too low & dying when stopping (traffic light, etc). read up on & cleaned IAC (major carbon) & decided since I had it that far apart to change plugs & wires. done, all back together & now have to put foot on gas to start/run--soon as you remove foot rpms start dropping(not instantaneous just immediately starts dropping) & engine dies.sounds good while running. no codes. any ideas guys? going to go get a volt meter tomorrow to check voltage..... dont know if noise from the EGR VR is normal or not?.... Thanks

 

what engine is in your truck and what model. lets do a quick and dirty test take the but of a screw driver and tap lightly on the IAC and see if it starts and idles. have you disconnected the battery since cleaning.

 

If you used TB cleaner on the IAC, it's probably dead now. Should have used WD-40. I'd replace it, cleaning doesn't always work anyway.

Noise from the EVR is normal, it's vacuum releasing when the engine is shut off.

I'd also pull the EGR valve and clean it. You can safely use TB cleaner on it, just don't get it on the diaphragm. Be prepared to replace the DPFE, it may also be crudded up. It can't be cleaned.