High emissions

[Linton]

I have only owned this s2 2.9 car for a few months and it seemed to run fine when i first got it but it has become difficult to start . You usually have to give it full throttle when cold and just down and up once on the throttle when warm . I have put new plugs in it which has helped but slow driving is a bit jerky and when i took it for it's m.o.t the emissions were high on the co's and the hydrocarbons and got worse the higher the revs went . If anyone's got any ideas as to what is wrong with it i would be very greatfull . Cheers Linton .

[mep12345]

Do the basics first, plugs, valve gaps, clean air filter, oil change, rotor arm and Dissey cap. Not all will need changing but check them and clean them. Then get the mixture checked at a garage. You'll be surprised how much difference each will make and the final one should bring it in once you've done the other stuff unless there is something seriously wrong

[Linton]

Thanks alot I will look into those things and see what happens . Cheers Linton.

[phillpot]

My two penneth worth...........

Clean the delicate little sensors in the air flow meters

Clean the connections on the electrical plugs on the air flow meters


Are the hoses from AFM's to throttle body ok (any little air leak will give problems)

Edited by phillpot on Sunday 10th May 07:24

[tango123]

A high HC is normally indicative of unburnt fuel, so all the advice is good . Check all ignition side , AFM etc a good fuel cleaner like Forte wont harm either .

[TVRees]

Here is also some info from a previous post, regarding cleaning those AFMs.

AFM cleaning

[mep12345]

phillpot said:

My two penneth worth...........

Clean the delicate little sensors in the air flow meters

Clean the connections on the electrical plugs on the air flow meters


Are the hoses from AFM's to throttle body ok (any little air leak will give problems)

Edited by phillpot on Sunday 10th May 07:24

Thanks Mike, forgot that bit to clean. Also make sure the leads have not been reversed. The one with four electrical connections should be on the top, the one with three on the bottom. Then when setting mixture you start with both bypass screws closed then gradually open top one until either fully open or mixture is in spec then move to bottom if you cannot achieve mixture on top bypass screw alone.

Wrt holes in the hoses, I agree they can make a huge difference but I found holed hoses tended to make the mixture weak. The mixture could of course have been set up with a leak here that has now been disturbed or stopped by proper fitment of the hoses.

[Linton]

Thanks to everyone for your advice. When i get a chance i will look into all those things. Cheers Linton.