Hi guys,
Its that time of year again for my 2000my xkr, time for it's annual check up the problem I have been having for the last 3 years (or 3 annual tests) is that here in the UK part of the emmission test is to rev to 3000 rpm and hold it for approx 30 seconds whilst the testing machine counts down and measures the nasty stuff coming out of the back, problem is it being an "R" it will not maintain 3000 rpm and it fluctuates so then the emmission testing machine says "restart at 3000 rpm and hold", as you can immagine it is a pain in the backside luckily i have an understanding test center so i was wondering how all you other lucky R owners get bye?, is there a bypass switch somewhere or can you pull a fuse.
thanks in anticipation
rrosscoe

 

Well that's a totally new one om me....??

 

I'm beginning to think that the province of Ontario and the UK are having a contest to come up with the most irrelevant tests to put a car though.

 

With the Transmission in Neutral the Revs are limited to 3000 RPM. You may be at that limit.

 

I think it's just to heat the cats up as they're not properly hot on a car that's stood idling. Not critical it's 3000 but I don't see why it would not happily rev at a steady rate. It should. There again, needs the tester to keep foot steady and maybe not good at doing that.

An alternative is to drive to get cats hot then emissions test immediately before they cool.

They only seem to do this revving if the car has already failed the fast test, and if it is failing that, then that may hint at an underlying problem. Something may be marginal i.e. not so bad as to flag codes but not really within the proper range.

I see nothing irrelevant about the test but then I know what it's testing and why...

 

Nearly time for test, it's tomorrow so will see what happens this year, just to make it clear it is the emission machine which says rev to 3000 rpm and to hold it for 30 seconds countdown and it resets itself if the revs drop or fluctuate too much which is happening as my engine hits 3000 rpm and then the limiter cuts in dropping revs below2700 ish then cuts out allowing engine to rev to 3000 again it is this fluctuating that constantly resets the testing machine that is the reason i am asking if there is a way of disabling the limiter, I know it is there to protect the engine from being thrashed to death boy racer style.
RRosscoe

 

I know of no way to disable the rev limiter. Yours is not the only S-type in the UK (stating the obvious) so how do all the others pass the same test?

Without hijacking the discussion or getting into one of my favourite rants over bungled emissions or safety tests, I can't see the relevance of measuring emissions specifically at 3K RPM while in neutral or park. For all it's other failings through misapplication of technology, the smog test here involves interrogation of the OBDII system looking for fault codes. The presumption is made that if no codes are present, all is well.

 

It is a XKR i have and i believe this may only apply to the supercharged vehicles, i would put a picture on my postings but it is not very clear as to how you do it.
RRosscoe

 

Sorry, forgot I was not in the S-type section but the point remains- yours is not the only such vehicle in the UK.

 

They don't measure at 3K. (The posts may mislead.)

They do check OBD MIL, for example. No need for a rant about things that are in fact not the way you're guessing!

 

MOT is 2500 rpm for 30 seconds. That should not trouble the limiter, but as it is a very abnormal operating condition for the engine it could well be that the ECM is trying to stabilise the parameters, causing varying emissions. Also, if you have disconnected the battery and not done enough drive cycles, the emissions will not have stabilised.

 

Panick over!
Sailed through this year, the tester used a light right foot so car behaved impecably,
just to put my US collegues in the picture here in the UK they do not touch the OBD readouts for any of the annual tests so if the readouts are correct but there is a air leak in the exhaust system the testing machine will through up a Lambda error so no pass,
anyway as said problem solved "untill next time eh"

regards to all and thanks for the interest
RRosscoe

 

They check the MIL, though, which would normally be on for that.