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SVA Fail
timcrasher - 21/4/04 at 12:16 PM

Hi guys,
Took my beast for its SVA today at Nottingham. It failed on just the Lambda reading ( just too high ), and the brake bias ( which was adjusted on site ).
The tester was very helpful and very complementary about my car, which made the whole process alot less stressful.
All you guys going for SVA tests this week, take lots off rubber edging stuff etc as the tester will let you cover any troublesome parts as you go through the test.
I'm off back to the MOT station tommorrow to have another play with the settings and will hopefully get retested next week!
I rang my exhaust supplier ( a well known feline branded kit maker ) for advise, because they said the exhaust system would pass, and was basically told it was my problem and to get lost.
But a phone call to Fisher sports cars was the total opposite. Helpfull advise and a pleasant manner even though I dont own one of his products. Top man!
Good luck to the rest of you
Cheers
Tim


britishtrident - 21/4/04 at 12:53 PM

Good products and good attitude go together.


Nick Davison - 21/4/04 at 01:08 PM

What was the problem with the brake bias? And what is your opinion of the Nottingham examiners, I have to use them sometime?
Nick


timcrasher - 21/4/04 at 02:41 PM

Hi Nick,
The brake bias adjuster I fitted just wanted an extra turn as I had to much rear bias.
The Nottingham SVA inspectors were fantastic and tried their best to get me through first time. We spent about fourty minutes adjusting the mixture etc, but just couldn't get the reading low enough. The tester looked almost as disappointed as me.


Lightning - 21/4/04 at 03:53 PM

You say adjusted the bias, do I take it that it was a bias bar and if so did you put in roll pins?
As you probably gather I have a bias bar and will soon be applying for SVA


ChrisBradley04 - 21/4/04 at 04:48 PM

Tim,
If you can't get lamda down but CO & HC are fine, then I would check for an exhaust leak. In the end my emissions failure was cured by using a pot of 'GunGum' on the exhaust joint

Sorry if I am teaching my granny....and all that.

Regards
Chris

www.fisherfury.com


britishtrident - 21/4/04 at 05:05 PM

Just had a high lambda fail on one of my other cars, suspecting the exhaust was drawing air I looked I found a pin hole in the welds in the exhaust down pipe.


spunky - 21/4/04 at 05:06 PM


Markp - 21/4/04 at 05:17 PM

I used Nottingham almost a year ago (how time flies!!!!!!!!!)

The examiners were very helpful, put you at ease and want the car to pass.

A good experiance at the time.

mark


timcrasher - 21/4/04 at 05:58 PM

Thanks for your suggestions guys.
I did check for leaks. but the examiner said that I needed to get more air bled into the exhaust to get a lower reading.
Steve,
I have a rotary bias valve fixed with a roll pin. I just needed to remove the roll pin, turn the knob and refit another pin.

Gonna experiment with the air valves in the cam cover tommorrow at the MOT station to see if that makes any difference.
Cheers
Tim


britishtrident - 21/4/04 at 06:33 PM

quote:
Originally posted by timcrasher
Thanks for your suggestions guys.
I did check for leaks. but the examiner said that I needed to get more air bled into the exhaust to get a lower reading.
Steve,

snip
Tim


High lambda alone usually caused by too much air -- either due to a weak mixture or more usually a pin hole somewhere in the exhaust down pipe.
See http://www.bobmckay.co.uk/p_emissions.html Basic fault finding for advanced emission test failures --point 5


Mk-Ninja - 21/4/04 at 06:53 PM

Hard luck Tim hope you get it sorted

The emissions is my main worry. Dont thing Im going to sleep tonight, mind you Ive got to set off at 5:30 so its not worth going to bed antway.
On my MOT the CO was very low but the HC was marginal, how do you lower the HC without affecting the CO too much.

Hope Im not talking gibberish here but cant think straight at present.


timcrasher - 21/4/04 at 07:57 PM

I will have another go with the mixture settings then.
The exhaust is deffinately not leaking, so I will richen things up, as the co and hc readings were very low.
Gordon good luck tommorrow. I had to get up at 5am. I didn't sleep at all, so I know what you're going through. But it will be fine.
Cheers
Tim


ChrisBradley04 - 21/4/04 at 09:47 PM

Gordon,
If CO and lamda were all in range, but HC is marginal then make sure that your cat is HOT as possible for the test. The hotter the cat the better it works. I did a few fast laps of the SVA centre, putting the engine under load , just before doing the test. I had my pipes glowing red

The worst case scenario is a bigger cat, which can be rented cheaply if required.

Good luck tommorow.

Regards
Chris

[Edited on 21/4/04 by ChrisBradley04]