So I get a ses light flash driving down the road. Checked my codes with my handy edge Evo unit and got p0221 " Tps circuit b malfunction or something like that. I cleared it and pulled up to the next light. It took off 1st gear 2nd and as soon as it shifted to third the Tc locked up " at 25 mph " so what's the deal ?

 

No idea bit here is a bump. TPS is throttle position sensor right? Is your acceleration normal?

 

Reason for thinking Tps is when I pulled the code it read p0221 and said throttle position sensor b fault ..... Or something like that. It feels kinda dead the first quarter of the way pressed down. But then kicks up like normal . The ses light is off since I cleared it. It runs fine but shifts from 2nd directly to locking up the t/c with out running 3rd gear. It's been raining here all day. Drove all day and was good, came home parked for 2hrs went back out and it started bout ten min after.

 

Man did I stump y'all on this one ?

 

I would start by pulling the pedal assembly and cleaning the TPS and IVS with some electronics cleaner. Sounds like your idle validation switch isn't kicking in just off idle as it should.

 

From the 1999 PowerTrain Control/Emissions Manual:
Code P0221...Throttle Switch B Circuit Performance. Probable cause: Failed pedal assembly.
More info: Fault Detection/Management:
1. Any detected malfunction of the AP sensor will illuminate the Check Engine Light...Federal Calibration Only.
2. An AP signal that is detected out of range high or low by the PCM will cause the engine to ignore the AP signal and will only allow the engine to operate at low idle.
3. If a disagreement in the state of idle validation switch (IVS) and AP sensor is detected by the PCM, the engine will only be allowed to operate at low idle.
High Input:
Causes:
A: Damaged Accelerator Pedal
B: AP sensor may not be seated properly
C. Damaged AP sensor
D. Short to power in harness.
E. Damaged PCM

Low Input:
Causes:
A. AP sensor not seated properly.
B. Damaged AP sensor.
C. Open harness.
D. Grounded harness.
E. Damaged PCM.

Hope this points you in the right direction. PM me if you need the troubleshooting section. I'll copy, and send as attach pdf.

jeff

 

Al and Jeff, thanks for all the suggestions and info on the topic. I was doing all the posting from my phone while at a wedding last night. The problem occurred on the way to the wedding.

So i don't mean to be repetitive but just for others and now I'm on my pc i can go through and explain more in detail.

I have been using my truck only once a week since Jan 1, due to out of town work. Its been running great with no issues. Arrived home tues afternoon and have been using it everyday since. Yesterday it started raining and the wife and i went out shopping for some things. Drove ob 20 to 30 mi into town and back. Truck ran great. Came home for 3hrs truck sat, fired it up to go tot the wedding. Drove out the drive way and hit the main road into town running ob 50 to 55 mph on my 80e tune from DP. Got behind a slow car doing the ole 35 to 45, 35 to 45 deal. Not staying at a steady speed my truck would drop OD down to 3rd then T/C would lock then hit OD then Shift back to 3rd then T/C then OD. Thus only due to the slow car who can't hold a steady speed. So i turned the OD off to keep it from shifting so much.
The car slowed to a stop and turned, i turned the OD back on and took off regularly. When i flipped the OD back on i seen the SES light come on then turn right off. Right away i checked my DTC's using my dash mounted Edge Evolution " which is only for digital gauges and code reader " It read p0221 "Throttle Switch B Circuit Performance." I cleared the code. Upon take off it shifted from 1st to 2nd then to 3rd for a split second then the T/C locked up almost the same time it shifted to 3rd. It did this all the way to the wedding. Even with the OD off or on and in Stk tune and 80e. After 4hrs of off time while at the wedding i fired it up and was ready for a long ride home. HAHA nope she ran perfectly normal the entire way back home..... roughly 20mi. WEIRD !

I noticed what felt like a bit of a delay upon acceleration in the pedal. Immediately i thought TPS. But if it is WHY would it still go accelerate fine but shift like that........

So back in 2010 i had what felt like a dead spot in my pedal. It would shutter or cut out when held at a certain spot. So i ordered a new one from ED. Installed it and had no issue till last summer. The dead spot came back so i put the old " original one " back in and it was fixed.

So Al and Jeff.... Thanks i am planning on cleaning the pedal assay but need a food write up on it if y'all can send me a link.

Jeff excuse my dumbness but "AP" whats the AP sensor where is it located and whats its purpose ? and why would this cause it to shift like i stated ? It idles fine and revs fine it just threw the code and started shifting all funky like i explained earlier above.

 

Normal TC lockup occurs after the shift into third gear except when hard into the throttle, in that case it locks the TC after second gear. Your PCM must think you have the pedal mashed down pretty hard. Try cleaning or replacing the TPS sensor.

 

Yea on the lockup i am fimilar with how it works. Normal driving ...... 1, 2, 3, then tc at about 35 to 40 unloaded and @ normal acceleration then od @ 45 to 50. After the ses flashed the TC would lock @ 25mph before or when shifting to 3rd @ normal acceleration.

Im about to run to the shop about a 5mi drive down the road. Id like to clean the tps sensor but can't find a write up on it.

 

I can't remember a write up on it honestly, but it's just a couple of bolts and unplug the connectors and the entire pedal assembly can come out. Or you could spray electronics cleaner up into the switches and pot, with the straw and possibly be able to clean then enough. I think once you look at it you will see how it comes out though.

Here are some pics for reference though in this thread.

https://www.ford-trucks.com/forums/9...ensor-fyi.html

 

AP is for the "Accelerator Pedal" sensor. It's purpose is to monitor the position of the throttle in a gas or diesel engine. The sensor is located under the dash driver's side. Check out this link:https://www.ford-trucks.com/forums/9...ensor-fyi.html
I would follow what others have stated and clean the sensor first before replacing.
Jeff

 

I assume the AP Sensor as you describe is the "TPS" Throttle Position Sensor. I read the link and and didn't see or catch anything referring to a AP sensor. It was all TPS. But any hoo i found a nice write up with pics on how to clean the entire pedal assy.

Took it out and used a light amount of contact cleaner and compressed air to clean the tab and button on the IVS and all the pivot points on the pedal assy its self, after removing the TPS. After cleaning i applied a decent amount of silicon spray to all the pivot points and to the tab and button on the IVS.

As for the TPS its self i couldn't find any way to really clean it...... the back of it where the pedal inserts in to it looked very clean and still had the factory white lube on it which was debris free and looked brand new. Its sealed very tight and couldn't even see how you could clean that part to be honest other than the connectors which looked awesome !

Re-installed and all is working fine. Like i mentioned after its episode on the way to the wedding all has been good. The drive home last night and to the shop this morning " Pre Pedal Assy Cleaning " was great and then back home from the shop " Post Cleaning " was great and the pedal felt greatly smoother.

My concern is most that i have read up on this issue with others if they get Code p0221 or dead pedal, it works or it doesn't . I haven't read anything describing a truck shifting the way mine did anywhere involving the p0221 code.

Im wondering also if chaffed od wires in the column could cause this ? idk haven't checked them but am planning on it as primitive maintenance.

 

The AP sensor and the TPS are the same thing. Just different terminology. Seems like the cleaning worked for you. That's great.
As long as the P0221 code doesn't come back your back in business.

jeff

 

Right on yea i figured. Well i hope the cleaning worked as the entire thing was not that dirty. My worry is what caused it to shift like that ????? If it was AP or TPS related id think the pedal would be dead or have a dead spot. Not cause it to run ok and shift from 2nd direct to tc lockup...... Im stumped and would like to figure that out as i said I've herd NO ONE with TPS prolbems or p0221 codes mention there tranny shifting funky. But many I'm the first !

 

If a disagreement in the state of idle validation switch (IVS) and AP sensor is detected by the PCM, the engine will only be allowed to operate at low idle meaning your limit of 25 mph. It could have been just a hickup in the monitoring that caused the light to get lit. You then got under there, cleaned it up and made sure the TPS was tight and secure. Cleared the code and it might not come back. If it does, then you'll need to troubleshoot further to find the discrepancy.
How many miles on the transmission? Have you ever done the trans flush or replaced the filter? If not, I'd complete a trans flush with new filter. Put a 3/8" in line Magna-Fine filter on the return line out of the cooler. Here's a link: https://www.ford-trucks.com/forums/1...and-video.html
I would also take a fluid sample and send it to Blackstone for analysis.
My E99 has 268,000 miles on the original trans works great. Never had a problem shifting and I tow a gooseneck horse trailer and haul around a 9.5' cabover camper. No repairs to the transmissions. I service the trans on a regular basis with oil analysis. Wear metals are constantly low and there is no trace of in-solubles.