Why does my MOT centre like to test my car cold?

[kalniel]

You go to all the fuel-wasting effort to get the engine nice and warm for a realistic smoke test reading and they then sit on the car for an hour before bothering to test. No surprise that the first smoke reading is close to 7.

The regulations state: "The engine oil temperature measured by a probe in the oil level dipstick tube is to be at least 80°C, or normal operating temperature if lower (60°C minimum). Testing an engine below normal operating temperature may affect the test result"

And all I get is a 'oil temperature not measured' on the report. Bah.

(average of next three tests was below threshold, so no problem, though it seems the italian tune ups in the preceding days didn't really have any effect on the figure from the previous year).

[Moby-Dick]

I@m sure I've seen that oil temp sender in a cup of tea at previous test centers

[Konan555]

It's amazing what a modern ECU can do. For instance, the 52 plate fiesta next to my old XR was able to perfectly mimic the Sierra's exhaust emissions during the test.

[Jay]

They did that with my diesel last time, cold start emission check.. what where they expecting to see?

[jon bda]

It's amazing what a modern ECU can do. For instance, the 52 plate fiesta next to my old XR was able to perfectly mimic the Sierra's exhaust emissions during the test.

Last MOT for my Laguna, its emmisions were suprisingly close to that of a Toyota Yaris that had just been mot'd...not bad for an old car with no cat...

[CAT-THE-FIFTH]

They are Lizard people.

[MadduckUK]

Last MOT for my Laguna, its emmisions were suprisingly close to that of a Toyota Yaris that had just been mot'd...not bad for an old car with no cat...

made it to the test centre as well, not bad for a renault

[jon bda]

made it to the test centre as well, not bad for a renault

Did me proud the Slaguna...still feel sad for driving her to the crusher when it hadn't ever let me down...

[jon bda]

They are Lizard people.

Lizard people that say you cannot drive your car until you please them...

[DanceswithUnix]

I believe it is common for a diesel ECU to run for the first few minutes from start in a low emissions mode (sorry, engine warm up mode *cough*) as some emissions tests are guaranteed to be done within 5 mins of cold engine start. Perhaps the garage assumes all cars do that, and think they are helping. Might work for derv, but I can't see how a petrol engine would give a good reading with a cold cat converter.