Emissions test
Emissions test
Author
Discussion

jonbarrett

Original Poster:

800 posts

232 months

Friday 27th June 2008
quotequote all
Just had an emissions test done prior to the MOT.

Left bank running perfectly. Right bank passed but running much richer. Tester suggested a missfire. Any one got a list of things I can look at in order. Coil packs and leads are relatively new and I plan to put new plugs in. Anything else I should be doing?

mooey

101 posts

233 months

Friday 27th June 2008
quotequote all
If you can, plug a laptop into the ecu and look at the faults (if any). Lambda sensor, throttle pot or positions maybe the culprit

trackcar

6,453 posts

256 months

Friday 27th June 2008
quotequote all
how much richer is much richer? have you got the figures to show us? I would suggest that if youve got a cerb that passes the emissions test on merit don't touch a thing!!

Ballsy

317 posts

247 months

Saturday 28th June 2008
quotequote all
May sound daft but have you checked the leads are correctly seated on the plugs? Some of them are a right pain to get on properly

Old Geezer

3,598 posts

224 months

Saturday 28th June 2008
quotequote all
Check the resistance of each lead and compare.
Then check the plugs the same.

Just replaced No6 lead on my V6 A8 (£30!) as it was causing huge problems!!
Unbelievable problems just for one duff lead, but it was 21k ohms instead of 5k!!

Steve

Mars

10,143 posts

244 months

Saturday 28th June 2008
quotequote all
How do people get through the emissions test? I managed to get through by massively advancing the ignition and reducing the fueling in the tested areas, and this was after taking the car for a run to heat up the catalysers to nuclear temps.

In the end the car passed on the tester's computer but it was getting too hot to wait for contection to the DVLA so the testing garage gave it a pass based on that.

It got through, legally, although not without a lot of hassle.

How does everyone else do it?

JensenA

5,671 posts

260 months

Saturday 28th June 2008
quotequote all
You go to a TVR friendly garage - say no more smile

Mars

10,143 posts

244 months

Saturday 28th June 2008
quotequote all
I did consider that but I couldn't believe EVERYONE had to go to dodgy lengths to pass. You don't hear of people failing and not being able to use their Cerb because they can't get it through, so I assume all (guessing) 600 remining Cerberas pass their MoT every year.

Does everyone go to a friendly TVR garage then? Doesn't anyone try to get through a more conventional way like I did? Is everyone too afraid to talk about it in case it devalues their car? To be honest, that last sentiment is why I wanted to get mine through conventionally because I felt that if I had to rely on someone else to bodge it through then I couldn't sell it with a clear conscience. I now know it's possible and I felt I could repeat the experience if called upon to so.

brogenville

941 posts

231 months

Saturday 28th June 2008
quotequote all
I had to buy a new cat, but with good lamda sensors, my 4.2 "just" passed a normal mot test. Ive got the printout somewhere.

Byker28i

92,358 posts

247 months

Sunday 29th June 2008
quotequote all
Not a problem with my 4.2. It's on the limit but passes with the cats in.

jonbarrett

Original Poster:

800 posts

232 months

Sunday 29th June 2008
quotequote all
Good news passed the MOT yesterday with no trouble. Here are the emissions figures on the pass sheet: CO=0.07%, HC=141ppm, Lambda=1.03. The right bank also passed but the HC figure was just under 200max.

She has new coils and new Magnacore leads. I will check the lead resistances just in case. She is also getting new Iridium plugs next week. I'll redo the emissions test to see if it makes a difference.