Throttle Control

[borgward]

2013 Fiesta 5 Speed Manual Hatch. 1.6 liter. I posted several years ago about throttle body control problem. Answers I got were that the $600 control had to be replace. not repairable. Moisture inside causing corrosion on contacts. Still have the problem sometimes. Usually happens after it rains or severe temperature change. I do not think it is throttle controller. Corrosion is not going to go away because I turn the ignition on and hold the throttle and brake pedal down for 20 seconds.

I am thinking it is the wiring harness connections. Found one at the throttle control. Where else does the harness have plugs and sockets between the throttle control and the throttle pedal inside the passenger compartment? What can I use to dry them out and what can I use to clean the tiny metal bits inside the connectors? What to use to keep moisture from getting in them. These connectors are similar to the ones on 3 gen Escorts. Up to 6 tiny pins and holes in each harness connector. On Escorts the pin connections tend to loose contact.

I can go months without having any problem. Once it happens I just turn the engine off, turn ignition on and hold the pedals down for 20 seconds and am then good for the next 6 months or until it rains a lot. That's easier than spending $600 for something I probably don't need.

 

[Dave9]

You could save us some work by linking products and showing pictures of suspect areas.

Which engine? Rock Auto only shows throttle bodies for the 1.6L SOHC for Canadian cars, but for the DOHC engine, they show a Cardone at a very reasonable $97:

https://www.rockauto.com/en/catalog/ford,2013,fiesta,1.6l+l4+dohc,1505322,fuel+&+air,throttle+body,6472

You can probably clean the throttle body electrical contacts using a cotton swab with metal polish (brasso, etc, with oxalic acid in it to eat at corrosion). The mating wire harness connector, "probably" has a colored plastic insert that you can pull out, to release the wires and contacts to get at them for cleaning.

I'd expect that goes back to your ECU, not likely to have a corrosion issue there unless you have a windshield leak, though I don't know where the ECU is located on those, but a leak of that big connector would tend to corrode more pins and manifest itself in more ways than just the throttle. I assume you have hooked up a scan tool that shows realtime data and it shows incorrect throttle position? If not I would do that before spending $100 or more on a throttle body.

Certainly, check the gas pedal connectors. Similar to throttle body you may get a cotton swab in one and be able to disassemble the mating connector by removing a plastic insert.

Dry them out? If there is water inside, just air drying or a fan if in a hurry but then you need to determine why water got in and then I'd think about using dielectric grease on them, and if the connectors have an o-ring seal that's shot, replace that too, or if the whole connector is badly corroded and an inexpensive pigtail you can replace, to replace it. Although this example isn't inexpensive for a mere connector, it might be one option:
https://www.rockauto.com/en/catalog/ford,2013,fiesta,1.6l+l4+dohc,1505322,electrical-connector,throttle+control+actuator+connector,15861

If the female pins for a connection are loose, you may be able to very gently, bend a "little" more tension into them. If you absolutely had to, you could put some RTV "sensor safe" (non-acid-cure) sealant on the outside as a cheap hack/fix, but I think I'd go for a color other than black on a black connector to make it easier to see, and I'd sooner try just dielectric grease and see how that works after cleaning.

 

[CourierDriver]

How did our pony cars ever get us to town in the

 

[clinebarger]

Ford has a TSB concerning throttle control issues.....TSB 13-11-15 involving 2011-2013 Fiesta.
"Some 2011-2013 Fiesta vehicles may exhibit an illuminated Wrench Lamp with DTC B1029:11 in the Instrument Panel Cluster (IPC). The vehicle may or may not exhibit lack of performance concerns, and DTCs P2126, P2127, or P2138 may be present in the Powertrain Control Module (PCM)."

Didn't even have to look up P2126 & P2127......Those a APPS 1 & 2 circuit fault codes! Have you scanned for DTC's?

 

[borgward]

B1029-11 Accelerator Pedal Sensor
P2127-00 Throttle?Pedal Position Sensor/switch E Circuit Low Enput
P2126-00 Throttle?Pedal Position Sensor/switch E Circuit Range/Performance
P2138-00 Throttle?Pedal Position Sensor/switch D / E Voltage Correlation

Additional Information
Malfunction indicator lamp (MIL) status OFF
Distancelled while MIL is activated 0 miles
Number of warm-ups since DTC's cleared 109
Distance traveled since DTC's cleared 2057.36

Cleared codes

B1029-11 Accelerator Pedal Sensor

Malfunction indicator lamp (MIL) status OFF
Distancelled while MIL is activated 0 miles
Number of warm-ups since DTC's cleared 1
Distance traveled since DTC's cleared 11.18