Throttle dropping out and complete loss of throttle

[Travis Belair]

Hello Everyone
I will be driving at a consistent throttle position and it will cut out and or increase at times. Sometimes it will drop out completely, car will idle, and have zero throttle response. I have new TB, Throttle position senor and throttle pedal. Previous owners mechanic installed for same issues. Here's the crazy thing. I been driving a couple years now and it is only when its warm out. Like we are seeing 70's and above and I am having issues. Not one issue for the last 3-5 months. I got codes today. P2121 and P2140. I also data log and logged data today. Sent it to Lito but he hasn't replied to my last 2-3 emails about cams and other upgrades. Any suggestions would greatly be appreciated.
Thanks
Travis

 

[Dino Dino Bambino]

Both are throttle pedal position sensor codes.

https://www.autocodes.com/p2121_ford.html

https://www.autocodes.com/p2140.html

 

[stkjock]

Was the TB motor/actuator replaced with the TB?

 

[86GT351]

Replace the throttle body. Simple

 

[Dino Dino Bambino]

Replace the throttle body. Simple

He's already replaced that plus the TPS and the accelerator pedal. The problem is that he still has accelerator pedal position sensor codes. Therefore the question is, was the sensor replaced or only the pedal?

 

[DieHarder]

Hello Everyone
I will be driving at a consistent throttle position and it will cut out and or increase at times. Sometimes it will drop out completely, car will idle, and have zero throttle response. I have new TB, Throttle position senor and throttle pedal. Previous owners mechanic installed for same issues. Here's the crazy thing. I been driving a couple years now and it is only when its warm out. Like we are seeing 70's and above and I am having issues. Not one issue for the last 3-5 months. I got codes today. P2121 and P2140. I also data log and logged data today. Sent it to Lito but he hasn't replied to my last 2-3 emails about cams and other upgrades. Any suggestions would greatly be appreciated.
Thanks
Travis

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Below might help:

DTC 2121 - TPP (Throttle/Pedal Position) Sensor/Switch D Circuit Range/Performance - The APP fault flag is set for sensor 1 by the PCM. Causes: APP sensor 1 is open, or shorted to ground or voltage. APP sensor signal circuits are shorted together. Damaged APP sensor. Damaged PCM. Use Pinpoint Test DK.

DTC 2140 - ETC (Electronic Throttle Control) Throttle Position Sensor E/F Voltage Correlation- Key on or engine running; the PCM detected the Throttle Position 'E' (TPE) and Throttle Position 'F' (TPF) sensors disagreed, or that the TPE sensor should not be in its detected position, or that the TPF sensor should not be in its detected position. Causes: ETC TP sensor connector is damaged or shorted. ETC TP sensor circuits shorted together in the wire harness. ETC TP sensor signal circuit is shorted to VREF (5v). ETC TP sensor is damaged or it has failed. PCM has failed.

Pinpoint Test DK - The test procedure for the Accelerator Pedal Position (APP) is to wriggle, shake, and bend small sections of the wiring harness while working from the sensor to the PCM. The resistance of the individual lines should be less than 5 ohms. I'd test from the pedal (TP - Throttle Position Sensor) to the PCM and the ETC (Electronic Throttle Control) to the PCM. See prints.

From your description sounds like you may have an intermittent condition that's heat related. Since it appears you've replaced all of the active components the only things left (other than bad parts) are wiring and the PCM. Given you're only having an issue when it's warm I'd lean towards wiring/connectors first; then PCM. That said I'd review the prints and check for continuity/ shorts/ opens of all related wiring. Remove and check connectors for pushed out pins and corrosion. If you have a VOM disconnect the connectors at the TB & Pedal; put the DVOM (Digital Volt Ohm Meter) on Ohms and trace/check each line. Check wiring for kinks/fraying/poor connections (wriggle them a bit).

Prints below should help. You may also need to create some jumpers as the DVOM needs a return path. Check for shorts between lines as well.

https://iihs.net/fsm/?d=40&f=Electronic Engine Controls - 4.6L.pdf&p=3

https://iihs.net/fsm/?d=40&f=Electronic Engine Controls - 4.6L.pdf&p=8

 

[86GT351]

He's already replaced that plus the TPS and the accelerator pedal. The problem is that he still has accelerator pedal position sensor codes. Therefore the question is, was the sensor replaced or only the pedal?

We see it all the time with aftermarket parts. If it is not a Ford part you are rolling the dice.

 

[Pentalab]

Which BRAND of TB is the replacement ? I replaced the oem twin 55mm TB, with a FRPP twin 62mm TB....and zero issues after 8 years.

 

[Rugermack]

I stay with all OEM ford parts for sensor/actuators, otherwise you become a great mechanic replacing aftermarket parts. I also have the FFRP twin trottle body 2.5 years with no problem.

 

[GlassTop09]

\

Below might help:

DTC 2121 - TPP (Throttle/Pedal Position) Sensor/Switch D Circuit Range/Performance - The APP fault flag is set for sensor 1 by the PCM. Causes: APP sensor 1 is open, or shorted to ground or voltage. APP sensor signal circuits are shorted together. Damaged APP sensor. Damaged PCM. Use Pinpoint Test DK.

DTC 2140 - ETC (Electronic Throttle Control) Throttle Position Sensor E/F Voltage Correlation- Key on or engine running; the PCM detected the Throttle Position 'E' (TPE) and Throttle Position 'F' (TPF) sensors disagreed, or that the TPE sensor should not be in its detected position, or that the TPF sensor should not be in its detected position. Causes: ETC TP sensor connector is damaged or shorted. ETC TP sensor circuits shorted together in the wire harness. ETC TP sensor signal circuit is shorted to VREF (5v). ETC TP sensor is damaged or it has failed. PCM has failed.

Pinpoint Test DK - The test procedure for the Accelerator Pedal Position (APP) is to wriggle, shake, and bend small sections of the wiring harness while working from the sensor to the PCM. The resistance of the individual lines should be less than 5 ohms. I'd test from the pedal (TP - Throttle Position Sensor) to the PCM and the ETC (Electronic Throttle Control) to the PCM. See prints.

From your description sounds like you may have an intermittent condition that's heat related. Since it appears you've replaced all of the active components the only things left (other than bad parts) are wiring and the PCM. Given you're only having an issue when it's warm I'd lean towards wiring/connectors first; then PCM. That said I'd review the prints and check for continuity/ shorts/ opens of all related wiring. Remove and check connectors for pushed out pins and corrosion. If you have a VOM disconnect the connectors at the TB & Pedal; put the DVOM (Digital Volt Ohm Meter) on Ohms and trace/check each line. Check wiring for kinks/fraying/poor connections (wriggle them a bit).

Prints below should help. You may also need to create some jumpers as the DVOM needs a return path. Check for shorts between lines as well.

https://iihs.net/fsm/?d=40&f=Electronic Engine Controls - 4.6L.pdf&p=3

https://iihs.net/fsm/?d=40&f=Electronic Engine Controls - 4.6L.pdf&p=8

^^^^This.............
I'd also highly suggest the liberal use of dielectric grease on every connector terminal that you disconnect to test all connector pins\wiring before reconnecting them going forward.