My 1998 Fiesta 1.25 Zetec failed the MOT, details here:
Exhaust emissions carbon monoxide content at idle excessive (7.3.2c)
Exhaust emissions carbon monoxide content after 2nd fast idle excessive (7.3.2b)
1st fast idle
CO% 0.64 (limit 0.3) FAIL
MC ppm 138 (limit 200) PASS
Lamda 0.99 (limit 1.09) PASS
2nd fast idle
CO% 1.2 (limit 0.3) FAIL
MC ppm 128 (limit 200) PASS
Lamda 0.97 (limit 1.09) PASS
natural idle
CO% 0.69 (limit 0.5) FAIL
Lamda/oxy sensor was changed 12 months ago after the same issues. It scraped through MOT on the limit. Exhaust has no holes, Cat has no holes.
Exhaust tip is black, oil is being burnt somewhere as I keep topping it up BUT it's not leaking externally. Water is ok, oil has just been changed, old oil wasn't milky or anything.
I'm thinking valve seals or something, but I've not got the knowledge of engine internals.
Thanks in advance
Steve
Exhaust emissions carbon monoxide content at idle excessive (7.3.2c)
Exhaust emissions carbon monoxide content after 2nd fast idle excessive (7.3.2b)
1st fast idle
CO% 0.64 (limit 0.3) FAIL
MC ppm 138 (limit 200) PASS
Lamda 0.99 (limit 1.09) PASS
2nd fast idle
CO% 1.2 (limit 0.3) FAIL
MC ppm 128 (limit 200) PASS
Lamda 0.97 (limit 1.09) PASS
natural idle
CO% 0.69 (limit 0.5) FAIL
Lamda/oxy sensor was changed 12 months ago after the same issues. It scraped through MOT on the limit. Exhaust has no holes, Cat has no holes.
Exhaust tip is black, oil is being burnt somewhere as I keep topping it up BUT it's not leaking externally. Water is ok, oil has just been changed, old oil wasn't milky or anything.
I'm thinking valve seals or something, but I've not got the knowledge of engine internals.
Thanks in advance
Steve