New lambda now getting fault code P0300

2001 PEUGEOT 106
40,000 MILES • 1.1L • 4 CYL • 2WD • MANUAL
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SUPERAL82
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Hi folks,

Short version....I don't know what I'm doing!

Long version....my girlfriends 2001 Peugeot 106 1.1 failed it's Mot on emissions with a new lambda given as the fix and the airbag light was on (have sorted the connection under the front seat) The exhaust was an advisory but was so rusted up I decided to change the lot as all three stages were falling to bits. The cat is in the front section of the exhaust and I replaced the post cat lambda with this one

http://www.eurocarparts.com/mobile/ecp/c/Peugeot_206_1.1_2001/p/car-parts/car-body-parts-and-car-exhaust/exhausts/lambda-sensor/?710545711&1&efcd803cf6433455d662c1a0858f892973bb0e10&000210

Since then the management light has been on and it's spluttering when cold. The fault code is P0300. I've checked the lambda has been reconnected properly and am now totally stuck as to how I've messed this up. Any help would be greatly appreciated
Nov 10, 2015 at 9:55 AM
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DOCHAGERTY
  • ASE Certified Mechanic
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  • ASE Certified Mechanic
Random multiple misfires is P0300
Was the code present before the work began?
Nov 10, 2015 at 10:09 AM
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SUPERAL82
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No. It's appeared after I've done the work and the spluttering when cold is post work also.
Nov 10, 2015 at 10:45 AM
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STRAILER
  • ASE Certified Mechanic
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  • ASE Certified Mechanic
Hi SuperAl82,

Are there holes in the exhaust before the cat? Because if so the system will draw in fresh air effectively causing the system to go rich which will cause the engine to misfire randomly.

Double check the wiring to the new O2 sensor.

Have you had a tune up recently? Are the plugs black?

Please let me know

Best, Ken
Nov 11, 2015 at 8:44 AM
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