981 MOT failure - emissions - Page 1 - Boxster/Cayman - PistonHeads UK

2016 981 Black Edition PDK (2.7) - 45,000 miles Tuesday; in for minor service, brake fluid & MOT. OPC called to say failed MOT test due to emissions and suggested new spark plugs would remedy it as they are due for change anyway. Additional £240 on top of the £650 already quoted for the service & BF and can't test again until Wednesday. Failed again. They now say that diags show O₂ sensor failed so are replacing that (under warranty). Part ordered and expected today. Fingers crossed it passes this time and I get it back later today. Is it unusual for a five year old car to fail on emissions? I've had many cars most far older and never had a failure before, even with +100k miles on them.

Quite common if the car isnt used much . Seeing lots of failures in the last few months as cars not being used Bottle of cat cleaner and a 20 min thrash before mot solves it.

Mine's been used at least a couple of times a week so not much standing about.

O2 sensors are a known failure point. Incidentally - are you getting the car up to temp when it goes out? If not, then cat cleaner and a nice, Rev-happy drive ought to do it.

LordGrover said: 2016 981 Black Edition PDK (2.7) - 45,000 miles Tuesday; in for minor service, brake fluid & MOT. OPC called to say failed MOT test due to emissions and suggested new spark plugs would remedy it as they are due for change anyway. Additional £240 on top of the £650 already quoted for the service & BF and can't test again until Wednesday. Failed again. They now say that diags show O? sensor failed so are replacing that (under warranty). Part ordered and expected today. Fingers crossed it passes this time and I get it back later today. Is it unusual for a five year old car to fail on emissions? I've had many cars most far older and never had a failure before, even with +100k miles on them. First thing to do after MOT emissions failure is connect it to PIWIS. Sensors failure is easy to spot on PIWIS. I'd ask for a discount on plugs which weren't required.

LordGrover said: Mine's been used at least a couple of times a week so not much standing about. Fingers crossed a cat hasnt failed?

Sensor has resolved the issue; it's passed. A bit miffed that they didn't replace that first before having me fork out £240 for plugs that may or may not had a bearing. Ah well, I suppose it's done now. I must say though, after three days in the Macan S loaner the 981 feels very low, loud and raw.

Cotswold Porsche alerted me to O2 sensor fail on one bank... it was out of calibration although the yellow light hadn't come on. Could feel difference in torque around 2.5k on the way home. Fuel cons improved over the next 100 miles or so. May have been at fault some years before then...

Cotswold Porsche alerted me to O2 sensor fail on one bank... it was out of calibration although the yellow light hadn't come on. Could feel difference in torque around 2.5k on the way home. Fuel cons improved over the next 100 miles or so. May have been at fault some years before then... (981)

LordGrover said: Sensor has resolved the issue; it's passed. A bit miffed that they didn't replace that first before having me fork out £240 for plugs that may or may not had a bearing. Ah well, I suppose it's done now. I must say though, after three days in the Macan S loaner the 981 feels very low, loud and raw. Shouldn't the plugs have been changed at the 4 year 40,000 mile major service any way....you haven't been charged (erm... ripped off) twice have you?

gtsralph said: First thing to do after MOT emissions failure is connect it to PIWIS. Sensors failure is easy to spot on PIWIS. I'd ask for a discount on plugs which weren't required. No, ask for free plugs or they can put the old ones back in as they got it wrong. I betcha if they did this they'd then say: "Hello sir, we put your old plugs back in but I'm afraid it failed emissions again and so it seems it was a combination of the sensor and the plugs. We've put the new plugs in and it's fine now but there's another £140 labour for switching the old ones in and out again. Credit card please."

Plugs hadn't been replaced in previous major service so due anyway - I just wanted a moan. Just North of £2,100 for the service, plugs, brake fluid and renew two year warranty. It's noticeably pulling stronger now, and oddly the stop/start is more active too. Prior to this service it was rare that it stopped, ever since it's quite keen to stop at every opportunity. Maybe it's coincidental that the ambient temps are increasing... Now let's have some decent top-down weather please. I'm freezing my nuts off when the lid's down at the moment.