gerlewislewis 0 Posted August 21, 2008 Hi guys, ive just failed my mot for the following reasons. (the prices in brackets are what ive been quoted to put them right, can someone advise me if the jobs are worth doing myself for the price they are quoting). Bulbs (£5) Rear discs (£99) Horn too quiet - like a noddy horn (£35) Idle speed too high (no price - 'we will have to look into it for you properly') Are these worth chewing myself? Im a bit confused as to idle speed, didnt know that could be a failure. My car idles at 1800 when cold, and about 800 when warm - its tricky to find a happy medium due to the lumpy cams. Are this discs just a quick swap or do I need to wind the calipers back etc? The horn - could this be a nightmare wiring problem - or more likely just a new unit? Cheers! Ger Share this post Link to post Share on other sites
Powers 13 Posted August 21, 2008 Bulbs about right. Rear discs are really easy to do, you can wind the pistons back by hand using a large flat headed screw driver. Cost around £40 per pair. Horn around £5 to buy a motorfactors one and can be changed in 15 mins. Also very easy. Idle speed - Drive the car there warm and lower the idle speed using the screw on the throttle body. But 800 sounds about perfect anyhow. Share this post Link to post Share on other sites
Tom Fenton 1,542 Posted August 21, 2008 Rear discs are really quite simple, personally I'd do these myself but it depends how confident you are. The pistons will need winding back in. Horn is not that difficult, there are two that work together, probably one of them has failed. If you pop out the passenger side headlight you will see the horns lurking behind the bumper on a bracket. Idle speed too high is an odd one. Did they allow it to fully warm up? 1800rpm does sound very fast when cold though, mine idles about 1300rpm when cold, and somewhere around 850rpm when hot. Share this post Link to post Share on other sites
welshpug 1,657 Posted August 21, 2008 Bulbs; lazy sod rear discs, should fit pads at the same time, I guess they said they're corroded/pitted? Discs either £10.25 or £16.50 each from GSF, pads £13.60 or £18.10 a set (all plus vat, BUT less any discount ) then about half hour to fit, pistons do need winding back, not really a bad price from the garage depending on their hourly rate and where they get parts. horn too quiet, probably the standard dying 1.9 gti compressor, you can get an airhorn kit for about £15 from Halfords, just use the compressor to replace the original. cant remember if your horn was in the engine bay or under the l/h headlamp. Idle speed, difficult one as its odd that it idles so high when cold but fine warm, would have thought they would test it when warm and not encounter that problem. Share this post Link to post Share on other sites
Bonzai 2 Posted August 21, 2008 surely they cant fail you for idle speed, it must be emmisions rated? did they give you a copy of the MOT fail sheet? you want to be quick about it anyway i think you have 7 or 10 days and you can have a free retest (they only test the bits you failed on) Share this post Link to post Share on other sites
gerlewislewis 0 Posted August 21, 2008 cheers guys - yeah the emissions are fine on the sheet, just says fail on idle speed - im going to go and see him on my lunch and quiz him about it. as for bulbs - im not too sure which ones - I thought they were fine - Ill check em too - but for £5 he may aswell do it! Share this post Link to post Share on other sites
jackherer 543 Posted August 21, 2008 surely they cant fail you for idle speed, it must be emmisions rated? I've seen emissions machines specifically ask the operator "Is the idle speed reasonable? Y/N" or words to that effect so its likely to be down to there discretion. Share this post Link to post Share on other sites
Miles 331 1 Cars Posted August 21, 2008 Before the emmissions test the car should be at running temp and the fan's should at least kick in once, Then the probe goes up the exhaust and the test carried out. The rear disc's have to be the most common item on any car as the bias is so little on the back they rarely work like the front's, Replace the Disc's and pads or one will bugger the other one up, And clean the carrier's as again these rust and stop the pads moving as they should. Horn as said, I go a complete Air Horn unit in Halfords for £20.00, no way would they say it's too quiet then Share this post Link to post Share on other sites
Tesstuff 222 Posted August 21, 2008 Is it the car in your avatar that failed ? p.s nice to see you changed your signature Miles, that 'subtle' spelling error drove me mental each time i saw it Share this post Link to post Share on other sites
gerlewislewis 0 Posted August 21, 2008 yes Tesstuff. The £99 is for discs only, £40 more required for pads. The idle was 1200, and he said he likes to see it around 900. Share this post Link to post Share on other sites
Bonzai 2 Posted August 21, 2008 i would be tempted to adjust the idle screw on the throttle body to pass the MOT and then adjust it back to how you like it after its passed. i had to do this with my car in january albeit with the more technological requirement of a laptop live adjusting the map on the emerald, and forgetting to press save Share this post Link to post Share on other sites
Miles 331 1 Cars Posted August 21, 2008 1200 rpm is fine, You are allowed to have a higher tick over for older car's this also helps with the emission's, Tell him to read up in his MOT book and pass it on that or call VOSA up Share this post Link to post Share on other sites
gerlewislewis 0 Posted August 22, 2008 (edited) Miles, is that in writing anywhere in the internet? The closest thing I could find is: http://www.motuk.co.uk/manual_730.htm if you search for the section titled: Engine speed and temperature but it doesnt say anything about older cars. Edited August 22, 2008 by gerlewislewis Share this post Link to post Share on other sites
Alastairh 47 Posted August 22, 2008 The £99 is for discs only, £40 more required for pads. Thats a joke frankly. All of those 3 things can be done easily under 2 hours. Share this post Link to post Share on other sites
Miles 331 1 Cars Posted August 22, 2008 Not sure if it say's it on the web, I just know 2 different MOT people and they have both said the same thing and said it's in the MOT book but allot of MOT'er's forget about it or don;t know about it and fail everything Share this post Link to post Share on other sites
gerlewislewis 0 Posted August 23, 2008 well i did the discs myself this morning £35 Horn £6.25 Ive adjusted the idle down low, but will put it a bit higher for after the MOT Finally, i gotta do the blubs - but for £5 im tempted to let him do it Share this post Link to post Share on other sites
Powers 13 Posted August 23, 2008 All sorted then. Good lad doing it yourself. Share this post Link to post Share on other sites