TPS, IAC testing DTC codes

[Vinnie P]

Tested my TPS and got high results 2.08v-10.51v and also checked the resistance at 3.46ohms-0.38ohms idle-wot. Is the TPS junk?
The CEL light is intermitent and the I pulled 124,335,336 and 337 codes KOEO. It also stalls when the engine is cold but I can feather the gas to keep it running. Low idle (500rpm) with engine warm and no stalling. Pulled off the IAC to clean and found the plunger will not stay closed tight to the second port. Should the plunger stay closed in the off position and is this the cause of the cold stalling?
With the many 300 codes, should I change the EGR control sensor first? When I searched this seemed to be the first recommendation.

 

[MrShorty]

It's early, but I don't think there's any way, even on a malfunctioning TPS (a simple variable resistor), that you should be measuring 10+ V for a TPS signal. The TPS is powered by Vref which is only 5V. What do get for Vref?
Note that, I think Vref also powers the PFE. A fault in Vref could also effect the PFE.
Are all of those codes KOEO codes, or are any of them continuous memory codes? If you don't know how to distinguish, review your instructions for the KOEO test.

 

[Vinnie P]

Bad battery in meter!

Thanks for the reply. Once I changed the battery in the meter, all was normal. I did read 0.91 at idle, so I will try tuning the sensor. I've changed the DPFE sensor and I'm waiting for a new IAC valve. I suspect all will be well after that.

 

[Glacier991]

Let us know how it all works out.

 

[Vinnie P]

Easy IAC change

Changing that valve was a snap and no more cold start stalling! Got a good price from rockauto.com for a motorcraft unit and even w/ shipping was less money than autozone's aftermarket one. Only problem was waiting but I feel better with an OE part. Thank you all for your help!