Olah!
The rangie has just failed the MOT on emisions.
Help!!
CO (%vol) Max Limit = 3,500 Actual Value = 0.211 - Pass HC (ppm vol) Max Limit = 1,200 Actual Value = 1493 - FAIL
What can i do to reduce it a tad? I have replaced all the HT leads since the MOT as she was running a bit lumpy. Its made a bit of difference, but she still isnt running right.
Plugs next?
Mark.
Change plugs, try a dose of injector cleaner, then an Italian tune up, RR engines are so lazy they never get thrashed properly to clean the gunk out!
Its not that far out is it?
Trouble is, she is sorned at the moment, and i cant use her on the road as she has no MOT.
Can i get some injector cleaner from HalFRAUDs?
Plugs every time
Cheers lads!!
with my old saab I found that the HC value was inversely proportinal to the CO - so failing on the HC meant it was running too lean, and vice versa. Or i had a vacuum leak. that cause the same thing (low CO, high HC)
On or around Fri, 30 Sep 2005 14:29:33 GMT, "Mark Solesbury" enlightened us thusly:
which engine/fuel setup? they can all be adjusted. Sometimes, high HC is caused by burning oil, but it can also be an odd single misfire or two, dumping unburnt fuel down the pipe. Plugs might well help.
Manual Ref: 7.3 page 5 M.o.I. B 2
If a vehicle meets the CO requirement at its normal idling speed, but fails the HC check, re-check the HC level at a high idle speed of 2000rpm. If the HC reading is then 1200ppm or less, the vehicle will meet both the CO and HC limits.
Was the 2000 rpm test done ?
If not, go back & have it re checked...
Visit The MOT Forum:
On or around 30 Sep 2005 16:38:14 -0700, "NT" enlightened us thusly:
I thought that only applied to certain vehicles?
I know there's an exemption for SU carbs, which are notorious for running rich at idle, if it won't pass at idle you can up the idle speed. CO and HC, ISTR.
The 2000 rpm test is for ALL vehicles (1/8/1975-31/7/1992) that meet CO, but HC too high.
when we take our V8 90 for MOT I adjust the mixture to make it leaner then richen it up after. I believe for our year one the limit CO is 4.5% but it runs best at about 6%. I think thats what it was.
Richard
On or around 1 Oct 2005 05:18:43 -0700, "NT" enlightened us thusly:
ah, right. The one for SU carbs is about meeting the CO as well - it's recognised that it's not always possible to tune an SU-carb engine to meet the appropriate levels.
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