Emissions decipher\diagnosis request

zapata

Hello all combustion engine wizards.

NCT Exhaust Emissions failed

Engine Oil Temperature 97 celcius

Low Idle _ _ _ CO 4.82 vol% _ _ _ (above 0.30% fail)
(750rpm) _ _ _HC 162 ppm

Lambda 1.00

High Idle _ _ _ _CO 0.41 vol% _ _ _ (above 0.20% fail)
(2,521rpm) _ _ _HC 33 ppm

2002 Mk4 Seat Ibiza 1.2 petrol 109,000 miles

There are a few threads on Volkswagen Polo but nothing for the Ibiza.

Thanks in advance.

Waterson

You need to check the running condition of the engine with scandata. Suspect a lambda sensor/catalyst fault or very bad misfire

zapata

I used Torque to read the error today.

Current Fault Log

---

P0420: Catalyst System Efficiency Below Threshold (Bank 1)

Pending Fault Log

---

P0130: O2 Sensor Circuit (Bank 1 Sensor 1)

dr.fuzzenstein

If that's CO, it would point towards bad combustion. Before doing anything else, it would he a good starting point to check spark plugs, leads and maybe coils.
Does it ever run on 3 cylinders?

And of course change your O2 sensor

zapata

It seems to run fine for a 1.2 . I don't have that long to know for sure though. I'll try to check the plugs for any tell tale signs over the weekend.
I could live with changing the o2 sensor but draw the line on the cat unless I find a good used one cheap.