If it fails, unplug and drive truck. It is a once in the life of the truck sensor most likely.

Now the CKP crank shaft sensor, spare may be handy. If it fails, truck will not run. Very bad if out in the field looking for remote repositories of relics.

 

It certainly is funny how just after reading the replies yesterday, my Disco decided to show me what else can go wrong!

Coming to a stop I watched the RPM's almost go down to zero and almost stall out... seems to happen every time I slow down for a stop light or stop sign. Also I noticed the RPMs were acting a little funny revving up and bogging down...

Glad it is a Long Weekend here in BC Time to crawl under the Discovery and muck about

 

Sounds like time to remove and clean IACV with carb clean, and the hole it fits into. Don't move the end of it, the computer handles that.

 

Hi Savannah Buzz,

Any pictures of exactly where it is located inside of a truck other than the diagrams available in RAVE or the Workshop Manual?

Thank you for your time and help

 

Locate air filter, a big square box. From there, the next thing is the MAF sensor, about $1400. Follow along the corrugated rubber hose and you come to the throttle body. Two sensor on the front side of it. One is in-line with the butterfly valve pivot rod, it is the Throttle Position Sensor (TPS). The other is the Idle Air Control Valve.

See, you could do this in the dark, but I'm skeered of the dark, so always carry a flashlight.

Oh, and there are pix in the RAVE, but they are black and white.

 

Hi Savannah Buzz,

Thank you! I found it and cleaned it with some Seafoam Spray cleaner... man was there a lot of crud everywhere! The vehicle was still stalling but after about 20 km (12 Miles) it was getting better and by evening it was no longer wanting to stall when I came to a stop. I may hit it again tomorrow... along with the speed sensor tear down and cleaning.

Thank you very much for your time and help

 

You will want to clean the bore it came out of also. Plus your throttle body butterfly valve, and the PCV port from valve cover to throttle body, it can get plugged. Ditto for PCV line on passenger side from valve cover to intake, and remove the "spiral noodle" oil separator on that valve cover and clean with same stuff.

 

The VSS also affect how the truck comes to a stop. The ECU boosts the idle a bit when it sees that the truck is dropping to a stop. If you have VSS disconnected, the engine speed can drop wen decelerating to a stop.

 

Hi Savannah Buzz,

I also cleaned the bore the IACV came out of, the throttle body butterfly valve (which looked cleanish compared to the IACV), and the PCV line from the valve cover to the throttle body, but not the passenger side PCV line side. Will do that today.

I also noticed someone left paper towel in my air filter box under the air filter as I took off the top for easier access... removed that as well

Now on to the VSS and the passenger PCV line and noodle

 

Thank you for the help and input. Will be removing, cleaning and disassembling the VSS today

Will report back with pictures as well