MAF meter might just being going bad. Hard to say for sure until you can hook up a scan tool and monitor MAF voltage against TPS voltage/Load %

 

Alright I'm pretty sure I have this nailed down. When I unplug the IAC the idle speed does not change. There is 12v to the IAC. IAC measures 9.8 ohms which is in the proper range. Pulled the IAC and the plunger does not move when voltage is applied. Tested on the bench with a 12v power supply. I can hear the solenoid click, but the plunger barely moves. Probably less than a millimeter. It is stuck in the almost closed position. This explains why the vehicle keeps running, but not great. If the valve opened up all the way I expect the engine would stall. It also makes sense that cleaning off the carbon changed things, but did not fix it. I'm pretty sure this part is $100 or better. I have plenty of other things to fix on the truck so I'm going to see if I can locate one from salvage.

 

Went to the salvage yard. Could not find an IAC that was the same. Will have to try another yard. Also replaced the old fuel filter and I could be mistaken, but it seems to idle a little smoother.
Also had the no start problem again due to the fuel pump not operating. Turned out to be the relay. Swapped it with the EEC relay and it almost started. Pulled the relays and banged on them to move things around inside. Put them back in and truck started fine. Replaced the relays for the EEC and fuel pump.
Also sprung a coolant leak at the temp sensor for the computer. It is in line with the heater hose. The tee fitting for the sensor is real rusted. I'm replacting all the parts so it will get a new temp sensor that helps control engine operation. Then I'm off to find an IAC.

 

I wanted to put the problem behind me and get on to other things so I bought a new IAC for $110. Idle is consistent now. I suspect my cold start idle problem will also be fixed. Will not know until next winter.

For everyones information. My IAC had proper voltage to it, ohmed out within spec, and did not affect idle when tapping on the housing. Never was able to see the valve move during any tests with the new or old IAC. Apparently it has to be in the vehicle and running for it to actually open and close the valve. Finally figured out that it was not working by unplugging it while the vehicle was running and there was no change in idle speed. With the new IAC the truck almost stalls when you unplug it.

Sometime in the future I'll get around to cleaning the intake better with Deep Creep, but probably not until I decide to change plugs. It's running too good right now to mess with. Would like to enjoy it for a while and get the drivetrain repairs done first.

 

 

On our EFI bikes you can short across 2 leads on the TPS plug to reset it. Then there is a procedure using the Throttle to set it up properly.
Also since you ran all that crap through pull your plugs and see how they look. I normally replace mind after a good cleaning of the intake. I clean mine each spring and I don't get heavy build up.