Ford Focus (1998 - 2004) - 03 1.6 Recurring engine warning light

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Mon 1 Jun 2009 22:13
03 1.6 Recurring engine warning light - T140Focus
Hi all

Some time ago my Focus 1.6 LX developed a fault.

The amber engine warning light illuminated and my fault reader gave a P04020 error code. My local garage has replaced the cat, the forwardand rear lambda sensors, temperature sensor and the fuel regulator. These were replaced (on fords recomendation) separately but on each occasion the warning light again came on again after about 50 miles. The light is again on now, the error code is the same as on previous occasions but we are running out of options and parts to replace.

The following info came from my memoscan

Fault Code - P04020 Generic Catalyst efficiency Below Threshold (Bank 1)


Freeze Frame info

trouble code - P0420

Fuel SYS1 CL, faulty HO2S
Fuel SYS2 CL, faulty HO2S
calc laod 56%
coolant 112 deg C
ST FTRM 1 -3.1
LT FTRM 1 -6.2

MAP (Kpa) 0
engine RPM 2703
Speed 78Km/h

Is the Map Kpa = 0 significant?

Any help with a diagnosis would be greatly appriciated
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Mon 1 Jun 2009 22:41
03 1.6 Recurring engine warning light - elekie&a/c doctor

Fault Code - P04020 Generic Catalyst efficiency Below Threshold (Bank 1)


This usually indicates an inefficient catalyst.Can I assume that the new cat fitted was a non genuine Ford part?
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Tue 2 Jun 2009 20:06
03 1.6 Recurring engine warning light - T140Focus
yes a non genuine ford part
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Tue 2 Jun 2009 22:42
03 1.6 Recurring engine warning light - elekie&a/c doctor
I think the only way to fix this is to fit a genuine Ford cat or one of the new EC type approved products which should reach the same quality as original part.Unfortunately these cheap cats are not up to scratch(!).hth
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Tue 2 Jun 2009 23:10
03 1.6 Recurring engine warning light - bell boy
it is illegal to fit a non approved cat on a vehicle after 2001 now
5000 quid fine for the seller too
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Thu 11 Jun 2009 13:37
03 1.6 Recurring engine warning light - Statia
Sounds like it's time to go back to seller and tell them they have sold you an illegal product and ask them what they want to do about it?
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