PX Ranger revving up and down while driving

[The Pariah]

Hi have a 2013 Ranger with no fault codes and everything is running fine - except it revs up and down constantly while driving - pls see clip https://youtu.be/4HH8d_t1ywI
Once you settle at a cruising speed it starts. It stops over 2000 rpm. Idling is fine, accelerating is fine. Starts & runs well.190,000km
MAF and MAP sensors are clean. Have read it could be EGR or SCV. Ford dealer says they have no idea where to start and I can see this costing a ton as they work through it crossing things off the list.
I have combed forums looking for exact same problem but no luck. Thought I should ask if anyone has had this exact same problem? before I let the dealership go HAM on it.
Any input welcome

[Trublu]

Do you actually here the engine altering revs or is just tacho fluctuating?

Possible causes could be vacuum leak, fuel delivery problems such as pressure, regulation, fuel pump, filters or injectors etc.

[The Pariah]

Thanks for the reply, Sorry didn't mention that the revs of the engine are rising up and down in synch with the tacho

[george87]

Take it to a diesel specialist and get your fuel pump tested and fuel filter inspected for metal filings.


Sent from my iPhone using Tapatalk

[The Pariah]

Thanks George hadn't considered that option

[The Pariah]

Just an up date for anyone who is interested
Problem solved - the auto transmission fluid was totally shot, completely cooked, the transmission cooler bypass valve needed replacing, probably a looong time ago by the state of the trans fluid.
Also they cleaned the EGR - absolutely filthy, completely choked up - something I knew should be done but never got around to it.
Cheers

[2013fordranger2013]

Hey mate did you find it only did this when warmed up ? Having the same issue so hope it's an easy fix with a service and new bypass valve

[33910ndl@gmail.com]

Just an up date for anyone who is interested
Problem solved - the auto transmission fluid was totally shot, completely cooked, the transmission cooler bypass valve needed replacing, probably a looong time ago by the state of the trans fluid.
Also they cleaned the EGR - absolutely filthy, completely choked up - something I knew should be done but never got around to it.
Cheers

This Definitely came through for me, my car is now running smooth, no vibration or Revs hunts.

Thanks man.

[Carlin]

I’m having the same problem with mine (330,xxx 2012 auto) I’m going to follow up the bypass valve now. I just replaced turbo and injectors thinking it was to do with that.

How did you figure out it was the bypass valve and how much did it cost to fix?

[Davros]

I’m having the same problem with mine (330,xxx 2012 auto) I’m going to follow up the bypass valve now. I just replaced turbo and injectors thinking it was to do with that.

How did you figure out it was the bypass valve and how much did it cost to fix?

So Carlin, what was your issue? Mine the same symptoms… Cheers, Dave

[Trublu]

I’m having the same problem with mine (330,xxx 2012 auto) I’m going to follow up the bypass valve now. I just replaced turbo and injectors thinking it was to do with that.

How did you figure out it was the bypass valve and how much did it cost to fix?

So Carlin, what was your issue? Mine the same symptoms… Cheers, Dave

Click on Carlin profile name and you will be able to send him an email with your question.