MOT Emissions Failure

Discussion and technical advice for 84-89 AW10 & AW11 MR2. 3A-LU, 4A-GE, 4A-GZE.

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dasher
Posts: 26
Joined: Sun Jan 09, 2005 9:14 pm
Location: Teesside

MOT Emissions Failure

Post by dasher »

Hi all,

I got my Mk1 T-bar MOT'd today, and everything was perfect except the emissions test. It got 9.488% CO where it should have been under 3.500%. The HC was OK, 834 (Max limit 1200). The past few years it's been well under on both.
The only thing i've changed from last year is a new exhaust (Mongoose from a Janspeed), but i wouldn't have thought that'd be the problem.

Any body have any ideas on what i should check? I've got 10 days before the free re-test runs out.

Cheers in advance,

Darren
dopiaza
Posts: 96
Joined: Wed Mar 16, 2005 4:33 pm
Location: Cirencester

Re: MOT Emissions Failure

Post by dopiaza »

Hi,

That's WAY high for emissions - the limit may be 3.5% but it should be more like 1% if it's set up correctly. Also would expect HC to be much lower, that points to unburnt fuel. How's your MPG? Is the car running smoothly?

Where are you in teesside? I'm there daily and could take a look at lunchtime of after work if you like.

Cheers,
Graham
Tiny
Posts: 3111
Joined: Fri Sep 21, 2007 7:00 pm
Location: Bordon

Re: MOT Emissions Failure

Post by Tiny »

1stly When was the last time you changed your Plugs/leads/dizzyrotar/cap

2ndly have you ever messed about with the mixture screw.

3rdly Have you replaced any of the vacuum hosing or is it still the original toyota stuff.

4thly was the car upto a decent hot temperature as the Waxstat may have still been open if they just drove it in cold. causing high Mixture and big emissions.
dasher
Posts: 26
Joined: Sun Jan 09, 2005 9:14 pm
Location: Teesside

Re: MOT Emissions Failure

Post by dasher »

Cheers guys,

I've just checked last years emission results & it got CO 2.58% (strangely with a max limit of 4.5%, have they lowered it?) & HC of 170.
So somethings definitely gone catastrophically wrong. For info it's been laid up over winter until about 5 weeks ago.
When i started it up for the first time, there was a fuel leak, and when investigated, it was a rubber fuel pipe that had virtually come off a rigid pipe close to the bulkhead/fuel filter. It was the smaller of the two pipes in that area, possibly a return from the fuel regulator (the regulator looks new & shiny so probably after market). At the time i just pushed the rubber pipe and it's spring clamp back firmly over the rigid pipe. Could this have caused a problem?
The engine seems to run as smoothly as it always has, but the idle is slightly higher at about 950rpm, and there probably is more of a smell of petrol, but it's hard to tell.

Hi Tiny
1. In the 4 years i've had the car (1st 2 years full bodywork restoration), the plugs, leads, dizzy rotar/cap have never been changed.
2. I've never touched the mixture screw. I don't know where it is.
3. Again i've never replaced any of the vacuum hosing, i assume it's original.
4. It was driven about 12 miles to MOT station, so was nicely warmed up.

Hi Graham,
The MPG seems OK but i haven't driven it that much in the last 5 weeks.
As above the engine seems to be running smoothly.
I'm in Guisborough during the day (but that's no use as the MOT has run out, so not in the MR2), but live in Eaglescliffe.
I will try inspecting/replacing Tiny's suggestion initially.

Cheers,
Darren
jon_st205
Posts: 618
Joined: Sun Feb 19, 2006 9:37 pm

Re: MOT Emissions Failure

Post by jon_st205 »

The big clue there is the aftermarket FPR, ditch it and pick up a stock one. Don't run it too much (not that you will with no MOT) with it overfuelling to that extent, you're literally washing the bores with fuel.

Jon
LimeyMk1
IMOC Committee
Posts: 11200
Joined: Thu Oct 04, 2007 9:28 am
Location: Gosport

Re: MOT Emissions Failure

Post by LimeyMk1 »

If the aftermarket FPR is adjustable you should be able to reduce the pressure in the rail a small amount and improve the fuelling. My Mk1 passed a couple of MoTs with a FSE FPR on it.

Got any piccies of the regulator. :-k

Have you checked your vacuum hoses for any leaks etc and is there one on the regulator?
Tiny
Posts: 3111
Joined: Fri Sep 21, 2007 7:00 pm
Location: Bordon

Re: MOT Emissions Failure

Post by Tiny »

What does the FPR look like take a pic as its may be all nice and shiney but be stock.

Hi Tiny
1. In the 4 years i've had the car (1st 2 years full bodywork restoration), the plugs, leads, dizzy rotar/cap have never been changed.


Get them changed
Plugs are about £4 each from Toyota
Leads Get a set of Magnecors £50 and if they ever go wrong they replace them for free for life
Dizzy Cap and rotor Arm.
Rotor arm is £8 Dizzy Cap £20 New Oring £2

2. I've never touched the mixture screw. I don't know where it is.


Next to the Map sensor
Have good read of this
http://www.ae86.hu/download/7/.
The Last page is the one you really need to take a look at. Called Join in the fun. Below 3600rpm the ECU takes into account the position of the Mixture screw and its well worth making sure your screw is in the correct place. :thumleft:


3. Again i've never replaced any of the vacuum hosing, i assume it's original.

Get it Replaced all of it Just buy 2m of the Silicon Vacuum hosing the same diameter of the original piping and then remove one peice at a time cut to length and refit. about 2 hours work and £10-15 max.


4. It was driven about 12 miles to MOT station, so was nicely warmed up.

Take it for a Damn good HArd thrash before hand easily 20miles to get it warm 4k+ rpm in the TVIS range and get it HOT.
dasher
Posts: 26
Joined: Sun Jan 09, 2005 9:14 pm
Location: Teesside

Re: MOT Emissions Failure

Post by dasher »

Cheers,
I'll try replacing the old bits and setting the mixture screw to zero.

The FPR is shown below. The pipe that partially came off is the one on the right hand side at the bulk head.




When it got mot'd i was late, so it got well caned all the way there.

Regards,

Darren

I've took the link to the pic out, as it's on my mobileme account, and i'm trying to work out how to make it public.
crazylegs
Posts: 2811
Joined: Tue Dec 14, 2004 4:13 pm
Location: Wiltshire

Re: MOT Emissions Failure

Post by crazylegs »

copy the pics to photobucket or similar. you can then get a link to post up
dasher
Posts: 26
Joined: Sun Jan 09, 2005 9:14 pm
Location: Teesside

Re: MOT Emissions Failure

Post by dasher »

Sorry guys, i've been out all night.

Hopefully you can view the FPR below.

http://www.flickr.com/photos/39660872@N08/3639921060/

Cheers,

Darren
LimeyMk1
IMOC Committee
Posts: 11200
Joined: Thu Oct 04, 2007 9:28 am
Location: Gosport

Re: MOT Emissions Failure

Post by LimeyMk1 »

Yup that's an FSE.

Where have you got the red hose plumbed to? It should go to one of the vacuum ports on the inlet manifold. If it's not the regulator will stay at a set pressure which is usually way too high.

The 2 nuts next to the red hose are part of the pressure adjustment, you take the top one off, loosen the lower and then there's a screw to adjust the pressure. I'll have to look up which way raises/lowers the pressure but Cass will scan and post the destructions up tomorrow. :thumleft:

Quick google and destructions are at the bottom of the page here:
http://www.fordmondeo.org/wiki/index.ph ... alve_HowTo
dasher
Posts: 26
Joined: Sun Jan 09, 2005 9:14 pm
Location: Teesside

Re: MOT Emissions Failure

Post by dasher »

Right cheers, I'll have a muck about with the FPR & mixture screw, but i'm a bit cynical because they should be at the same settings as they were last year.

Darren
Andy_J
Posts: 23
Joined: Sun Aug 03, 2008 8:35 pm
Location: Inverness, Scotland

Re: MOT Emissions Failure

Post by Andy_J »

Darren

If the car has been laid up your fuel will have gone off and will cause the emissions to go way out. Get the old fuel out the tank and put some new fuel in the tank

Had a similar problem a few years ago with my lotus. Fresh tank of fuel and it passed the emissions test with no other changes

Andrew
dasher
Posts: 26
Joined: Sun Jan 09, 2005 9:14 pm
Location: Teesside

Re: MOT Emissions Failure

Post by dasher »

Hi Andrew,

There wasn't much fuel left in, so it's had virtually a full tank of V-Power added.

Darren
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