Ford focus 55 plate - Error code p0240 on focus

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Sat 3 Jul 2021 08:46
Ford focus 55 plate - Error code p0240 on focus - Lisa-marie

So the engine light came on, I've run a diagnostics check and it came up

Fault 01 pending 01, error code p0420. I've done some research and seen its

Likely the catalytic converter needing replacing but wondered if anyone had any

Advice or experience with the same thing. Catalytic converter replacement sounds

Really expensive and I'm not sure the car is even worth much.

Incase these are helpful...

It's a 55 plate

1.6 petrol

91,127 miles on the clock

Passed mot in April with no advisories

Recently serviced

Any help greatly appreciated

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Sat 3 Jul 2021 08:56
Ford focus 55 plate - Error code p0240 on focus - elekie&a/c doctor
Yes , it’s a catalyst efficiency fault code . I would leave it alone and not do anything. If the car passed the test , wait for the next mot check .
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Sat 3 Jul 2021 09:44
Ford focus 55 plate - Error code p0240 on focus - bathtub tom
Yes , it’s a catalyst efficiency fault code . I would leave it alone and not do anything. If the car passed the test , wait for the next mot check .

Wouldn't the EML be a fail?

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Sat 3 Jul 2021 10:16
Ford focus 55 plate - Error code p0240 on focus - elekie&a/c doctor
Eml light on would be a fail for mot , but resetting the system just prior to the test would be enough to pass . This fault code usually takes a while to reappear.
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Sat 3 Jul 2021 08:59
Ford focus 55 plate - Error code p0240 on focus - Railroad.

P0420 is generated when the o2 sensor before the catalyst and the one after the catalyst (known as B1S1 and B1S2) are giving readings that are too similar, indicating that the catalyst is not doing its job. The pre cat sensor should give a switching reading between 0.1v and 0.9v. The post cat reading should be pretty level at around 0.45v. You most likely need a new catalyst.

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Sat 3 Jul 2021 09:59
Ford focus 55 plate - Error code p0240 on focus - Galaxy

I'd take the car for a really good run, particularly if it normally only does shortish journeys.

Give it a good "Italian Tune!"

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Sun 4 Jul 2021 03:16
Ford focus 55 plate - Error code p0240 on focus - edlithgow

youtu.be/RAC0E6apXq0

Not too much irritating rock music (for a US automotive video)

Scotty Kilmer reckons you can wash them. IIRC he just dumped the cat in a bucket with laundry detergent, but I daresay there are alternatives, (Id be tempted to try old brake fluid, though AFAIK that isnt a recommended procedure)

Never done that, of course, since I've never had a car with a catalyst, but I've back flushed a non-cat system I thought might be blocked, by sticking a garden hose in the back with the front end disconnected.

Got some debris and a lot of black stuff out.

Thinner in the petrol (see below) less plausible because it'll mostly be burned

www.youtube.com/watch?v=ZlPadYU2mPg

I'd say none of these tricks are very likely to be worth the trouble, and wont be attractive if you are not into DIY.

If you can sneak it through a test before the light comes back on after a reset, that's probably the way to go. and only consider cat replacement when you absolutely have to

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Sun 4 Jul 2021 14:21
Ford focus 55 plate - Error code p0240 on focus - Xileno

I think the last time the subject of cleaning cats came up, the thread attracted, well, shall we say some strongly opposing views...

I wouldn't think a cat for a Ford is going to be too expensive, if the rest of the car is good then it might pay to get it replaced?

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