Failed Emissions Test

Originally Posted by oldminiman
I took the 1982 Series 3 County SWB in for a French Control Tech today and received a 2 month referral on emission. The Petrol 2.25 Ltr has a reassonably new Weber but gave a CO2 reading of 7.3% I had adjusted the mixture using my old Falcon tester and then discvered that the spark plugs were just about in but not tight. The deposits were dark brown and I must admit to being a bit shocked but on returning home I was able to srew the mixture screw quite a way out and again usin gthe Old Falcon tester got a reading below 1%. I kept fiddling and it flutuated.

What I have noticed this week is on deceleration I am getting a rattle in the inlet or exhaust manifold area. At first I thought it t be the heat shield but once removed the noise remained. I decided t change the plugs and on restatrting the rattle stopped only to return later. I am a bit foxed and have booked it into a local garage on Tuesday. I have noticed the temperature guage is high having repalced the thrmo recently to get it down and now the rad cap. There is no sign of water in the oil or abnormal seam from the exhaust, so although I initially thought the head gasket may have gone apart from the engines temperature fluctuating, the engine it self is not ecessively hot and it may well be the voltage regulator causing the guage to malfuntion.

So we still have the funny rattle beneath the carb and the excessive CO2 and a flutuating temperature guage. Any one had similar problems. The previous owner gave me the CO2 reading from a couple of years ago sayi ng that the teter was shocked at it's low reading, 0.6%, well he wouldn't be now at 7.3%

Oddly my previous posting on Brakes and suspension didn't even get a comment during the test and all the reat of the car was A1, just

POLLUTION!!

Today, Saturday, I have cleaned up the original plugs and replaced them, checked the timing, spot on, removed the carb and tightend the adaptor, noticed an exhast leak at it's joint eith manifold, missed by the French mechanic and quite bad, refitted the carb and fitted the choke cable correctly which had not been tightened and was frayed. Unfortunately whoever fitted the Webber fitted a new cable for the choke, I would prefer to go back t the original but it is too short, I will find a way once this current problem is solved. I then reset the mixture using a colour tune plug. The rattle in the area of the manifolds has decreased but not dissappeared although it was quite on first start up. Removed the Colour tune and after replacing the correct plug I Put the Falcon gas Analizing meter on and she sat at about 4% + on tickover, blip the throttle and up she went to 7% hold throttle at about 2000 RPM for a minute and she drops back to around 2.5% and stays there. I am taking it in Tuesday for a CO2 test which I suspect it will now pass and then in for a MOT again. Of course I will tighten and seal the manifold jointon the exhaust.

have you checked all the tappet clearences, point gaps, plug gaps and timing recently? I'd do all that an then see if the emmisions are still rubbish. if that doesnt help i'd recommend cleaning and painting the chassis, won't help the emmisions problems but it'll keep you busy!!

Hi

All checked and spot on. It has a Luminisions electronic ignition so no points, timing spot on and steady. I have done some more today including removing the carb and checking the butterfly for play plus attaching the choke cable correctly. I used a colour tune to reset the mixture and then checked it on a Falcon gas analizer which showed on tick over 4%, blip the throttle and it shoots up to 6%+ and then run it at 2000rpm and it drops back t 2% Co2. I am having it checked on Tuesday and if my adjustmet are correct it should be ok, fingers crossed. I found that the exhaust was leaking at it's joint with the manidold so once cold will tighten theat up. Of course they missed that during the test entirely.