2016 Ford Fiesta 1.0 Ecoboost Titanium - Oxygen Sensor

Hi Andy
My engine light as come on and I have realized that this could be dirty fuel that is causing the problem. Ran a diagnostic on the car and the error is "O2(Oxygen Sensor) Sensor Signal Stuck Rich - Bank 1, Sensor 1" is there a way to clean this sensor without removing it.

Many thanks
Cedric

P2196 is usually a failed rather than dirty sensor. It’s unlikely any fuel system cleaner poured into the fuel tank will restore sensor function. If you’re going through the trouble of removing the sensor, have a new one ready to install. IIRC, the 1.0 upstream sensor is as easy as an oxygen sensor is to replace. I don’t know how sensitive Fords are but budget sensors can cause problems in other cars. Motorcraft or direct fit Bosch or Denso from a reputable source. Lots of fakes out there.

Hopefully P0420 doesn’t reflect permanent damage to the cat. Then hopefully the situation was caused by a faulty sensor. Otherwise there’s more work to sort the rich running condition when there’s a functioning sensor in place to guide further diagnostics.

Sixto
2013 SE 1.6 hatchback 135K miles

You also have to look into - if the P-420 condition persists - in having to replace that catalyst - many times from feedback in shops - the P0420 fail actually comes from the blocking occurring in the media of the catalyst pipe housing that honeycomb - it's plugged - that happens before it sets the P0420 because of the sensor upstream got smacked with debris from it failing - the deceleration you have done in ordinary driving closes off the intakes' throttle plate - but air can still arrive to the engine as engine braking - thru the tailpipe - and if the catalyst failed - that carbon and soot from it can get sucked back into the motor and that is thru where that sensor is mounted the exhaust manifold.

Since it gets so hot back there - it can fuse this onto the sensor and it's media too...

So if you can, monitor that vacuum in the intake manifold after replacing that sensor - a clean exhaust (non restricted) one lets the engine show 20in Hg at idle and as you drive 35MPH on to about 50MPH will be around 15~18 in Hg on regular smooth open pavement no hills.

It's when the manifold vacuum drops excessively and the engine acts sluggish and seems to be under more of a load that normal, you may have more work ahead of you due to the damaged pipe and the possibility of the plugging that goes with it.

Hi Everyone
Apologies for the late response, so I never got to changing or cleaning the oxygen sensor as yet. I now see its starting to affect the drive performance and its gotten quite thirsty on the fuel side. If I drive the vehicle slowly, no issues, when I try and accelerate the engine feels like its cutting off / heavy jerking, I then release the accelerator and the car is back to normal. The cost of the sensor is quite expensive in South Africa, R5500.00. Do you think I have caused further damage or do I need to just replace the sensor or will cleaning help.

many thanks

IF this was in the USA mostly those whom have these issues would try the easier method of; they would switch to a different brand of fuel and use their premium blend (Hi-octane) to let the system drive itself clean while on their highway commutes.

Then after a few tankfuls and the problem persists - then they'd have a more serious concern and possibly an investment into some type of repair.

One thing I did not mention earlier and this may help - have you checked your MAP and MAF sensors? Might want to investigate for dirt and or debris blocking them from sensing the proper air-flow and vacuum - so this might mean you're getting erratic performance due to their signals showing something else that affects your engines performance.

Here's a thread that can help you...
https://www.fordfiesta.org/threads/spark-plug-adapter-size.9668/post-27369

Hi
I spoke to an exhaust shop yesterday and they confirmed that it's the cat and I need to remove it

Keep us posted on this...let us know how it goes. Cat replacements are not cheap.

Sure will do, they say that the CAT is blocked, will let you know, I decided not to replace it but rather remove it. I hope that's the problem

Hi Handy Andy
Hope you are well, apologies for the late response.

I eventually had the catalytic convertor removed, both the oxygen sensor and catalytic convertor warnings were gone and the car was running much better, unfortunately the jerk / misfire was still there, decided to remove my plugs and inspect them and found plug 3 was cracked replaced that and car ran well for a bit but the problem came back. I then knew that the coil that goes over the plug needed to be replaced. I decided to replace it and sell the car as the mileage was hitting on 200 000 kms. I have now replaced the vehile with an Ecosport Titanium.

Thanks!

Mile of Smiles - hope this delivers, and give you the performance you deserve and return costs that the "actual lack thereof needed" in maintenance costs like you had previously in the other one.

200,000km or even in Miles - that's quite a feat and only that as some of the service you helped with. So with the next owner - perhaps a simple timing belt an water pump change will give them another 200,000km more of smiles per the miles...