Emissions mot issue

Wellhappy · Post by **Wellhappy** » Mon Apr 24, 2023 1:03 pm

Hey so the new lude went for the MOT today and passed on everything BAR emissions by 2 points, now I’m lost as I have never had a car fail on them, so now I’m really not sure what to do to bring them down ?? Any one have any ideas at all ?

Post by **Drax** » Mon Apr 24, 2023 1:10 pm

common thing is spark plugs for this in my experience, try that first.
after that, it could be your o2 sensor on its way out.

do you know if it has a catalytic converter fitted still? if a previous owner has fitted and left on a decat pipe, that will likely fail an emmisions test

Wellhappy · Post by **Wellhappy** » Mon Apr 24, 2023 1:23 pm

Fantastic thank you

and yes the cat is fitted (near the front which I found odd)… I will plug in and check the o2, thanks again

Scott560 · Post by **Scott560** » Mon Apr 24, 2023 1:44 pm

Is this the one you recently picked up?

It hasn't passed an MOT in 3 years, and done hardly any miles in that time either according to the history. At the minimum, fresh oil/oil filter/plugs/air filter, clean out the dizzy cap (to check your points haven't rusted to nothing) and fresh fuel and a decent run before the MOT test should help out a lot. A bottle of injector cleaner for good measure as well. If you can't drive it, at the least leave it idling for extended periods until you can take it for the next MOT.

Cats are always at the front of exhausts - they need the heat from the exhaust to help the chemical reaction, hottest at the front of course closest to engine.

Scott560 · Post by **Scott560** » Mon Apr 24, 2023 1:48 pm

MOT history shows the following fail:

Exhaust Lambda reading after 2nd fast idle outside specified limits (8.2.1.2 (c))

Wellhappy · Post by **Wellhappy** » Mon Apr 24, 2023 1:54 pm

Scott560 wrote: ↑
Mon Apr 24, 2023 1:48 pm
MOT history shows the following fail:

Exhaust Lambda reading after 2nd fast idle outside specified limits (8.2.1.2 (c))

yep first attempt was lower … fast idle

air fuel ratio so could me maf sensor ?

Wellhappy · Post by **Wellhappy** » Mon Apr 24, 2023 1:56 pm

Scott560 wrote: ↑
Mon Apr 24, 2023 1:44 pm
Is this the one you recently picked up?

It hasn't passed an MOT in 3 years, and done hardly any miles in that time either according to the history. At the minimum, fresh oil/oil filter/plugs/air filter, clean out the dizzy cap (to check your points haven't rusted to nothing) and fresh fuel and a decent run before the MOT test should help out a lot. A bottle of injector cleaner for good measure as well. If you can't drive it, at the least leave it idling for extended periods until you can take it for the next MOT.

Cats are always at the front of exhausts - they need the heat from the exhaust to help the chemical reaction, hottest at the front of course closest to engine.

I did reply to this but not sure why it didn’t post lol maybe my phone but anyway yea it’s the new one I picked up, I will try the above and report back fella thank you

Scott560 · Post by **Scott560** » Mon Apr 24, 2023 3:12 pm

No worries. The MOT history doesn't make for pleasant reading, so hopefully you have lots of time/space/ability to put it all right if you plan to keep the car. It's an UPHILL struggle from here to keep these ~25year old cars going, especially the ones that have been used most of their lives and have done 100k+.

The engines and drivetrains will easily see over 100k , but only if you looked after it. Picking it up in an unknown state or if it hasn't had any work done for a few years is not the best starting point I'm afraid.

Wellhappy · Post by **Wellhappy** » Mon Apr 24, 2023 3:40 pm

Scott560 wrote: ↑
Mon Apr 24, 2023 3:12 pm
No worries. The MOT history doesn't make for pleasant reading, so hopefully you have lots of time/space/ability to put it all right if you plan to keep the car. It's an UPHILL struggle from here to keep these ~25year old cars going, especially the ones that have been used most of their lives and have done 100k+.

The engines and drivetrains will easily see over 100k , but only if you looked after it. Picking it up in an unknown state or if it hasn't had any work done for a few years is not the best starting point I'm afraid.

all of what’s on the advisory list is being sorted today and tomorrow then a full service and a re mot … then replace parts that could lead to issues, new de cat exhaust going on anyway … tbh I wanted a car that’s not perfect as I now have the time to work on it and get it back to it’s former glory

and build up from there

The good thing is all Honda service history up to a few years ago and the water pump and belts all changed at 123000

Post by **vanzep** » Mon Apr 24, 2023 5:30 pm

good plan - get it on the road as a rolling resto (just like the rest of us)

i normally put in some fuel line cleaner to help with emmisions - wurth petrol saver is a good one..but there are plenty out there to choose from. Old fuel could be an issue but its easy to drain it out - its just one 14mm bolt at the rear of the tank on the passenger side.
good luck with the re-mot