MOT - Engine Oil temperature. VOSA

I wrote to VOSA on behalf of the forum regarding the non-use of oil temp measurement during the MOT.

This is a copy of our correspondence. I would be interested to hear any views on their response.


Hi,

As site administrator for www.tbar.com (a forum for MGF and MGTF owners), I
have noticed a growing number of Mot failures, caused by marginal emmission
fails.

From the car owners' viewpoint, a common complaint is that they feel that
the Mot tester has not allowed the engine to become sufficiently hot before
checking emmission levels.

Indeed, having looked at some of the Mot emmission readouts it is clear
that not oil temperature, but instead a visual check on the water
temperature gauge, has been used to check engine temperature.

In fact, it seems to be common useage, if not standard practice, that the
oil temperature sensor is disabled by the tester.
This, I suspect is down to time saving by the tester.
Is this not causing many marginal emmission failures due to the car still
running in partial 'choke' conditions?
This appears to be born out by the number of owners who drive the car for a
short time and return to the test station to then pass the emmission test.


Specific to our cars, are a couple of important points.

1/.The water cooling system temperature gauge moves very quickly to the
normal level.(Within 5 minutes of starting from cold). At this point the
thermostat will still be closed.

2/. The car, as standard has an oil temperature gauge, and it takes 10-15
minutes of driving before the gauge reads 60 degrees or over.

What is VOSA's viewpoint on this non-useage of the oil temperature sensor?
Why are testers not using all the equipment provided?

Yours,
David Fisher

MOT Technical
Standards/VIA
Sent by: John M To
Corcoran/RTE/VIA Enquiries/VIA@VIA
cc
Mark J Evans/HQ/VIA@VIA, MOT
10/05/2011 09:10 Technical Standards/VIA@VIA, Shaun
P Martin/RTE/VIA@VIA, James D
Brandon/RTE/VIA@VIA
Subject
Re: Fw: MOT - Engine Oil
temperature.(Document link:
Enquiries)









We are not aware of an issue with MG (or any other vehicle) marginally
failing the emissions test. As it an MG, I presume the query is in relation
to spark ignition emissions and in particular those vehicles fitted with a
catalytic converter.
The procedures in the Passenger and Light Goods Vehicle Inspection Manual
(IM) have been designed to give every vehicle the opportunity to be at the
correct operating conditions required to meet the emission requirements of
the MOT test and we do not have evidence to suggest any particular vehicle
is disadvantaged.

Section 7.3 of the IM details the Method of Inspection for this type of
emissions check.

The initial check is the Basic Emissions Test (BET) which a check against
common emission limits. There is no requirement to use any specific
temperature measuring device for this test and a vehicle cannot fail the
emissions test on the BET result alone.

If a vehicle does not meet the BET limits then a Full cat test using
vehicle specific limits must be carried out and an oil temperature
measuring device should be used. However the IM does make allowance for
vehicles where it is not possible/practical to use one.

If a vehicle does not meet the limits on the initial full cat test then a
second "fast test" is carried out but only after engine preconditioning
has been carried out to ensure that the cat is "lit" and has had a
reasonable opportunity to be at an optimum operating temperature. By the
time the second fast idle test is carried out it is likely that the engine
will be at it's normal operating temperature.

If an NT attempts to carry out an emission test with out the engine being
at the correct operating temperature then it is probable that the vehicle
will not, initially, meet the required limits and the exhaust gas analyzer
will "force" a second fast idle test. This is not in the interests of the
VTS as it adds more time to the test and our experience is that most NTs
are aware of this and ensure that the vehicle is at the correct operating
temperature for the test.

Though not always possible it is advantageous to present the vehicle at
operating temperature and close to the appointed time. Most VTS would then
carry out the emission test at the start of the MOT

These procedures have been in use for some time and we do not have evidence
from VTS or vehicle presenters to suggest that vehicles are failing the
emissions test unjustifiably. However, VOSA is responsible for
administering the MOT scheme and takes non-compliance with scheme
procedures very seriously. If a vehicle has been failed incorrectly then a
presenter has the right of appeal using form VT17 (which can be obtained
from any vehicle test station) or, if preferred, can complain in writing to
the local area office.

The latter is kept on file and may be used as intelligence data for
allocating enforcement resources such as unannounced visits where VOSA
examiners retest recently tested vehicles or 'mystery shopper' visits.


MOT Standards Team

Roadworthiness and Testing Policy Group

vey interesting reading, ( the right of appeal) the trouble is we know it but joe public dosent, and i dont care what garage it is , they will fail most cars on a whim just to generate money in the hope that the driver pays to have the work done. my last mot fail for the mgf (by kwick fit) was so vague that i took it for a second opion at a local garage and they couldnt see a problem for what the examiner failed it on

rayb wrote: vey interesting reading, ( the right of appeal) the trouble is we know it but joe public dosent, and i dont care what garage it is , they will fail most cars on a whim just to generate money in the hope that the driver pays to have the work done. my last mot fail for the mgf (by kwick fit) was so vague that i took it for a second opion at a local garage and they couldnt see a problem for what the examiner failed it on

Got to agree. I think there seems to be a bit of a 'head in the sand' attitude in the reply, to be honest.:shrug:

david aiketgate wrote:

rayb wrote: vey interesting reading, ( the right of appeal) the trouble is we know it but joe public dosent, and i dont care what garage it is , they will fail most cars on a whim just to generate money in the hope that the driver pays to have the work done. my last mot fail for the mgf (by kwick fit) was so vague that i took it for a second opion at a local garage and they couldnt see a problem for what the examiner failed it on

Got to agree. I think there seems to be a bit of a 'head in the sand' attitude in the reply, to be honest.:shrug:

Yep - the 'we don't see any car being disadvantaged attitude' is a pile of crock! ANY car that isn't up to operating temp would have issues! It just so happens that the way they measure ours is COMPLETELY wrong as the water gets up to temp far earlier than the oil temp....

It pretty much echos what I was told by a VOSA official that if procedures are not followed by examiners there is a right to appeal.
Chris

adamelphick wrote:

david aiketgate wrote:

rayb wrote: vey interesting reading, ( the right of appeal) the trouble is we know it but joe public dosent, and i dont care what garage it is , they will fail most cars on a whim just to generate money in the hope that the driver pays to have the work done. my last mot fail for the mgf (by kwick fit) was so vague that i took it for a second opion at a local garage and they couldnt see a problem for what the examiner failed it on

Got to agree. I think there seems to be a bit of a 'head in the sand' attitude in the reply, to be honest.:shrug:

Yep - the 'we don't see any car being disadvantaged attitude' is a pile of crock! ANY car that isn't up to operating temp would have issues! It just so happens that the way they measure ours is COMPLETELY wrong as the water gets up to temp far earlier than the oil temp....

It will be interesting to see what happens at my upcoming MOT, although Peter does it right!. i'll get a picture of the sensor in question if I can.

It's interesting that they say customers should be encouraged to bring their cars in warm, as the tester I used first tests the emissions last, so the car has been sitting for around 30 - 40 mins before being tested..

cjj wrote: It's interesting that they say customers should be encouraged to bring their cars in warm, as the tester I used first tests the emissions last, so the car has been sitting for around 30 - 40 mins before being tested..

There's definitely a difference between Vosa's idea of what happens at a test, and my experience over the years.
Than God,I've now found a good tester!

Your emission fail clearly said oil temp bypassed -Why? The sensor goes down the dipstick tube, and it's even at the same end of the car as the exhaust, FFS!

My F failed today on emissions!
Oil temp measurement by-passed!
Tempreture gauge showed engine warm!
CO< 0.30% vol
reading 0.39% vol!
time of test 10.57 (booked for 2pm)
time of call 14.41!
I'd have gone in at lunch time and taken it out for a blast if he'd called sooner.
Sting in the tail - I blew a fuse last night and descovered this morning on the way to the test that this fuse control the oil temp gauge so there was no reading on the gauge.

talkingcars wrote: My F failed today on emissions!
Oil temp measurement by-passed!
Tempreture gauge showed engine warm!
CO< 0.30% vol
reading 0.39% vol!
time of test 10.57 (booked for 2pm)
time of call 14.41!
I'd have gone in at lunch time and taken it out for a blast if he'd called sooner.
Sting in the tail - I blew a fuse last night and descovered this morning on the way to the test that this fuse control the oil temp gauge so there was no reading on the gauge.

Interesting. How do you think that stacks against what VOSA thinks happens?

Did you ask them why they didn't use the oil temp sensor?

I only managed to get there as they shut and after a long day I couldn't remeber the story. I am also a bit weary of being too confrontational as they are more than resonable and will let little things go, they are also resonable with payment, they did my steering gatiors and rebleed my brakes as well as the MOT but let me take the car without payment until all the work is done.

They had left the printout in the car so I was able to look at it.

I sorted the oil gauge tonight so will be pointing this out tommorow when I get there.