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Crazy_C
Thursday 20th May 2010, 00:37
Was just wondering, would a decat cause the lambda light to come on occasionally? Cos when I boot it, the lambda light comes on, but if I have a few days of steady driving, it goes off again, and it's only been like this since the decat, so it's the only thing I can think of, but just thought I'd check.


Also, I'm getting rid of the muffler box at some point too, will that have an affect on the lambda light?

Cheers

p fandango
Thursday 20th May 2010, 06:42
you should have only the one lamba sensor pre-cat so no it won't affect the emmissions light, same with the silencer

Crazy_C
Thursday 20th May 2010, 14:25
Must be one of the hoses leaking slightly when I boot it then. Cheers

TenaciousC
Saturday 22nd May 2010, 21:48
Lambda (ecu) light will come on for a number of reasons. This is not necessary a Lamba sensor issue. Check ECU fault code log to find cause. I have exactly the same issue caused by occasional overboost where the light will come on after booting it and stay lit for a few days. See this thread. (http://www.vpcuk.org/forums/showthread.php?t=27651)

Removing the CAT on the 850 shouldn't have any direct bearing as there is only one Pre-Cat sensor. The 70 series has one either side of the cat.

Cheers

C

Crazy_C
Saturday 22nd May 2010, 23:43
Yea, I did a test run today on my way back from work checking the boost gauge, and when it's boosting over 14psi, which it'll occasionally do when it's cold.

martybelfastt5
Wednesday 26th May 2010, 21:20
sorry for hijack how does the decat feel compared to before?

woody
Friday 28th May 2010, 10:54
sorry for hijack how does the decat feel compared to before?

Good question, I'm keen to do this mod!

p fandango
Friday 28th May 2010, 11:14
certainly alot better with a decat, the revs pick-up alot quicker & for the £20-30 to get it done well worth the money

Crazy_C
Sunday 30th May 2010, 17:38
Yea, really does make an improvement, much better throttle control too :) I'm gonna get the muffler removed too at some point for a straight through pipe :)

watchmytracer
Friday 4th June 2010, 21:17
how does this decat and straight through affect the car come mot ?

Jimmie
Friday 4th June 2010, 21:34
Fail.

Crazy_C
Friday 4th June 2010, 22:03
Mine still passes emissions at the moment with just a decat. Only just though lol

pigfight
Saturday 5th June 2010, 21:26
mine failed miserably with a decat!! (tried all the usual tricks: forte gas treatment, redex fuel treatment, a few miles of 'spirited' driving to get really hot!! etc.) so had to have the cat refitted, and theres a definate loss of power, so im now in the market for a race cat!
anyone got any pointers on what to go for? or will a universal 200 cell off of 'fleecebay' do the job?

Crazy_C
Saturday 5th June 2010, 21:27
Pointer on what to go for - Get mates who are MOT testers LOL