Ford Focus 2002 1.6 pet - Ford focus 02 - To change cat or not?

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Sun 6 Apr 2014 20:46
Ford Focus 2002 1.6 pet - Ford focus 02 - To change cat or not? - danfocus

Hi guys,

I have owned this car for a few months and have been getting the same problem where by the EML comes on after about 100 miles and stays on until reset. I'm suspecting its the cat but I don't want to start spending money changing bits unnecessarily, so I would be very interested to hear anybody elses thoughts...

  • Error code: P0420
  • Dashboard trick: DTC9318, battery and alternator have good voltages (also read that this is consistent with a knackered cat)
  • It looks like the front Lambda has been replaced fairly recently with a genuine ford part, maybe the previous owner was trying to fix this problem...before passing it onto gullible me!
  • Car is at 100,000 miles
  • Had an emisions test done which showed the lambda at 1.01 which is an MOT pass
  • Since I've had the car i've replaced: cam belt, speed sensor, air/fuel filters
  • Cleaned the idle control valve
  • Drives OK, MPG and power not as good as I would expect but don't really have much experience as my other car is a tuned up mini!
  • Makes a slightly unusual sound but not like its blowing, also I can cover the exhaust with a rag quite easily.
  • Also, the headlights flicker very slightly when the revs come down to idle, but otherwise I don't know of any other problems.

That's everything I can think of, thanks in advance if anybody can help.

Kind regards, Dan

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Sun 6 Apr 2014 21:03
Ford Focus 2002 1.6 pet - Ford focus 02 - To change cat or not? - elekie&a/c doctor

P0420 is a common cat efficiency code.The only permanent fix is a new (genuine)Ford cat.Probably more than the value of the car.An aftermarket cat will probably be a temporary fix ,it will put the light out for a few months .As you have found out,it does not affect the mot emissions test.I would be inclined to leave it alone,The engine mil light is not part of the mot test.

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Mon 7 Apr 2014 14:55
Ford Focus 2002 1.6 pet - Ford focus 02 - To change cat or not? - Railroad.
P0420 is generated when the pre and post lambda sensor readings are too similar which usually indicates that the catalyst efficiency is poor. As previously said, a new cat may be where you're going with this.
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