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Adi82
19-01-2006, 11:46
My MOT is due soon and i have a decat pipe on my 94 williams clio. Im guessing it wont pass the emissions test, can anyone confirm this? I have the cat still so i can put it back on, just a pain as most of the bolts have rusted badly.

steveos_16valver
19-01-2006, 11:52
leave the cat bypass on and if it fails put the cat back on as you get a free retest within 1 day

black williams
19-01-2006, 11:52
yes it will need the cat back on for mot mate

Riley
19-01-2006, 11:56
i just tried puttin myne threw mot with de-cat, not a hope lol cat back on straight threw no problems

Rich
19-01-2006, 11:58
hmmm i passed a spot check emissions without the cat on riley! must be different readings or something :?

Riley
19-01-2006, 12:01
tbh rich i think shes running rich, 200miles to the tank full at the mo :( sob sob.

gonna get valve clearances done hopefully that may cure it

Rich
19-01-2006, 12:20
if you get the readings from the emissions i'm sure someone on here can tellou straight away.

yeah valve clearances might be a good idea as she was getting a little tappy when i had her.

might be new lambda time though :cry:

Chris H
19-01-2006, 12:25
valve clearences? Is this a mk3 fiesta?

stew
19-01-2006, 13:09
LOL @ Chris!

Unless its a C or D type engine it aint "valve clearences" as they use hydraulic followers!

C or D type use rocker arms which can be adjusted!


Normally worn/defective hydraulic tappets. Mine are fooked at the moment. One of my pet hates with an engine. Will be sorted when Chris_H gets his paws on it! :wink:

Chris H
19-01-2006, 13:13
E and K engines and J's and a few more are manual adjustment clearences.

willy 0329
21-01-2006, 13:04
i think this is my old car and it failed last time with the de cat but passed no probs with the cat

badger
21-01-2006, 22:29
had this prob with a vts not long ago- use some injector cleaner and go for a good fast blast as i was told to by the tester and it went straght throw. it worth a try anyway

Tom_16v
23-01-2006, 18:50
'94 should pass easy with a de-cat.

emmisions limits are fairly high for pre '95 (m reg and earlier) cars.

my valver's passed with the de-cat on for the last 3 years.....

GTI-Russ
24-01-2006, 15:05
I'm thinking of gettin mine de-cated after my MOT in April, but can you feel/ hear much of a difference? I'm guessing it unleash's a few bhp otherwise no one would be doing it?

Smokey McPot
24-01-2006, 15:14
'94 should pass easy with a de-cat.

emmisions limits are fairly high for pre '95 (m reg and earlier) cars.

my valver's passed with the de-cat on for the last 3 years.....

My Willy didnt.

Tommo
24-01-2006, 16:08
'94 should pass easy with a de-cat.

emmisions limits are fairly high for pre '95 (m reg and earlier) cars.

my valver's passed with the de-cat on for the last 3 years.....

My Willy didnt.

Mine didn't pass either and it's '94. Had to buy a new CAT.... :(

Chris H
24-01-2006, 17:18
well toms wrong on that one.

its 31st august 1992 it has to meet cat test criteria

stew
24-01-2006, 18:04
Spot on as always chris!

August 92 is the date.

Is there much difference in the limits?

Chris H
24-01-2006, 18:45
pre 31st aug

3.5% co
1200ppm HC's

post 31st

0.5% co
200 ppm hc's