P0221- Replaced APP

[PSDEng]

Got a p0221 code last weekend while driving, simple enough I ordered a new sensor, Dorman p/n 699-200 from RockAuto, it came in on Thursday and put it in. I didn't drive the truck until today. After waiting in line at the car wash for 25 minutes I went to pull in and the code re-appeared with the same symptoms. Pulled the code again and wouldn't you know it....p0221 :cursing:

What's then next step here fellas? Could the IVS be causing this, or is it time for a new pedal?

The truck is a 97 cclb all stock except for an intake and exhaust.

Any and all help is greatly appreciated.

-Nick

 

[old man dave]

So. what are the symptoms? P0221 is Idle Validation Switch fail, not APP fail.

 

[PSDEng]

P0221 - Throttle/Pedal Position Sensor/Switch 'B' Circuit Range/Performance Problem

This is exactly what came up on my AE. Sorry, I should have put in the title that I replaced the TPS, my haste got the better of me.

The truck doesn't always register the pedal, and when it does it lugs a little bit while going through the gears. I hear the click of the IVS, and since the code is a TPS that is what I replaced.

 

[old man dave]

IVS exact replacement switch is available from onlinecomponents.com. NOT available from Ford. P/N SS22BW32-330Y (Eaton) complete with mounting bracket and stamped "Ford". $16+shipping or buy the whole pedal assembly from Ford for $400. May need to adjust IVS after installation.

Thanks to DesertRancher who researched the switch and located a supplier.

Idle Validation Switch failure is usually failure to accelerate from idle bacause the IVS is stuck and does not signal PCM to accelerate with TPS imput.

Onlinecomponents.com only has a limited number of switches and may not be restocking after they run out. So order now if you need one.

 

[PSDEng]

Thank you sir, I will order the piece from onlinecomponents and cross my fingers that it works.

Fwiw, right now on RockAuto the entire pedal assembly is $290 and it's the Ford part.

Could I check the voltage at pins 8 and 27 to verify that the IVS is the actual problem? ie.-if pin 27 sees no voltage at idle would that indicate that the IVS is, in fact, the issue?

 

[Patrick Feeley]

I would just disconnect the IVS connector and see if the switch closes (and stays closed) when the pedal is anywhere "off-idle". Cheers!

 

[old man dave]

As Patrick says you can check out the IVS with a meter to watch opening and closing.

Sometimes you can adjust the IVS action so it works, the switch does not always reset to closed because it is not being fully operated. The IVS contact can also develop a high resistance and not pass a signal that the PCM can read.

Also the Dorman replacement TPS units are a little shakey on quality control, have gotten a couple of bad ones. Ford units read about 4-500 ohms resistance at idle and about 4500 ohms at full throttle. The Dorman units read 5000 ohms at full throttle and can have an initial resistance of over 1100 ohms at idle position. The good ones seem to have about 500 ohms at idle position. This will give a jumpy throttle response when going from idle to some throttle input when the IVS operates and turns on TPS sensing.

RockAuto is selling the pedal assemblies a whole lot cheaper than my local (un)friendly Ford dealer apparently. :naughty:

 

[PSDEng]

Thanks for the input guys, it's much appreciated. I ordered the IVS from onlinecomponents.com (thanks old man dave for the link!)

It is scheduled to arrive tomorrow and I'll install it and see how it works. If my problems still persist I'll try another TPS, from Ford this time, and if I still have problems after that I might just have to break down and get a whole new pedal.