MOT PASS but with high emissions

[joey]

so gentlemen, this is an account of the day...

went to down to the local Halfords for the MOT test and it initially failed on seat bushings (never knew it could fail on this) but I told the guy to put the seats all the way back and this passed it ,they also replaced a number plate bulb...


the shocker was the emissions were all double what the should have been..I had about 30 mins earlier out a bottle of STP injector cleaner in but didn't have a chance to "open her up"....maybe some crap got dislodged and blocked an injector...really not sure..if felt fine though...

the chaps at Halfords suggested a "spirited run" down the A3 so thats exactly what I did...

so we did the gas test again and it passed by the skin of its teeth..phew!

so my question is where do I look first to deal with this issue?

my initial thoughts were

1 )cat two years old, but suspect a cheap one..

2) mixture..running rich MAF? or any suggestions would appreciated.

3) poor ignition, plugs? leads?

4) air filter..although this was new 4k ago so although i'm not ruling it out its unlikely..

5) oil contaminated by fuel?..


they did all say though otherwise a lovely clean car..

aceman need to order some bushings from you! have been delaying that TBH it looks like a pain of a job..

cheers

joe

 

[Brian H]

Does you temp needle sit bang in the middle of the gauge? Reason I ask is that the thermostats are prone to breaking and then the cars run too cool, causing the mixture to be incorrect.

BTW sounds like you have a friendly MOT tester

 

[joey]

Brian..

It does!....

Never above never below...

Give that man a cigar

 

[t-tony]

Hey Joey, when they tested the emissions did they test the oil temperature was up to 80 deg. If not that's where a lot of cars fail when they should not.

 

[GazHyde]

went to down to the local Halfords for the MOT test

I used them once, and they failed my car for all sorts of stuff, and handed me a quote of astronomical proportions to fix it... Never again!

 

[joey]

You know what..normally I would agree with that ,but they were really nice about it and Re tested it 3 times to get the reading that would pass it ..running it at different revs to see where the best reading was..

My experience was good in Guilford..

What's more they recommended a bmw specialist in camberly who I had already been told about by a trusted source to diagnose it..so seems they weren't after my cash..

I think it just needed a good run to get the temp up..

I am going to change the water pump and thermostat at the next service though..

 

[joey]

Tony ,

Not sure if they checked the oil temp..but considering they did the emissions test right at the end when the car was cooled down I'm going to say no..so a couple of factors at play possibly..

Brian's suggestion on the thermostat def needs investigating further though..

 

[t-tony]

Tony ,

Not sure if they checked the oil temp..but considering they did the emissions test right at the end when the car was cooled down I'm going to say no..so a couple of factors at play possibly..

Brian's suggestion on the thermostat def needs investigating further though..

Definitely agree on Brian's comment Joe. The thing about testing the oil temp is my personal drum to beat (as a tester myself) it really bugs me that cars fail when they should not. It's really only down to laziness.

 

[Tufarlian]

Doing the emission test when the engine has started to cool down is a no no.
The place I use for MOTs told me ages ago to make sure the car is properly up to temperature when I bring it in.
If I arrive on time it goes straight into the bay and they do the emission test first.

 

[zedonist]

Hi Joey,

Best get it on diagnostic, common M44 problems that will cause this are cam sensor, and the oxygen sensor ( should change at high mileage) a diagnostic May pick up a faulty sensor but then again not one that is at the extremes but just in, so bear in mind.

Air leaks post MAF, look at induct pipes, and like mine the injector seals were worn and the injectors dirty.

Decent fuel, I always run the highest octane non leaded, and use red ex every four full tanks.

First off, check your air filter, is it clean? Dirty filter will affect the mixture but the MAF should correct this, worth a look, plugs if old can have either too large or too small a gap, this could cause burn efficiencies, due to timing of the spark.

The good thing is it passed so you have 12 months to review it, just start with diagnostics first, then if no codes start on the low cost items.

There have been a number of guys that have emptied the cat of filter material and still passed the MOT with an M44, so don't go this route until sure.

Although I am still inclined to think the car was not warm enough for the test, as this engine does run rich at start up.

 

[Aceman]

Hey Joey they are not that bad to fit and take about an hour per seat taking your time. I have plenty in stock so whenever you are ready click the link below;

http://zroadster.org/z3-bushes-purchase-page/

 

[joey]

Thanks chaps ,

As always helpful and informative replies..

I did do a bit of web research but you can't beat advice from actual owners!..

The car runs great but then I have very few points of reference having driven only 3 other z's a 2.8 and a 2.2 and one other 1.9 so I really
don't know what a really good M44 should feel like..as the other was on 110k..and felt tired and loose in the steering also mine is an auto and they were all manuals , I have enough common sense to know nothing serious or dangerous is wrong with the car it's just that I want it running and looking 100% most "regular owners" would consider it tip top i'm sure...I reckon it's at 90% if that makes any sense ,i'm the same with my bikes and guitars!

I think I need to sit down ,go through the history and decide on a schedule of Work over the next year...

Water pump and thermostat right at the top of the "non service items" along with new plugs and leads at the next service ..

I have an asnu guy to clean the injectors and will do that on the service after..

and then I will look at ball joints and bushings in the front, rear coils springs and suspension components..

this should bring the car to as close as optimal as possible before then looking at any possible remap,induction or "performance mods"

£2400 was the original purchase price..with by the time i am done another £1000 spent on bits and bobs, the result will be a Z I know for a FACT is in perfect condition, time and money well spent IMO and she still only has 60k on the clock..

cheers

joe

p.s thanks aceman will do..just putting it off until dry weather!..

 

[GazHyde]

You know what..normally I would agree with that ,but they were really nice about it and Re tested it 3 times to get the reading that would pass it ..running it at different revs to see where the best reading was.

I'm glad someone has had a positive experience with them, and I'm sure they are not all as bad as my local Swindon branch!

 

[zedonist]

I went to have the tracking done after i lowered mine, I thought waste of time getting a 4 wheel alignment as no adjustment on the rear, but for some reason it seemed to phase the Halfords guy, because it was lowered, he gave me the keys back and said it needs to be done on hunter equipment, took it to Kwik Fit in Stafford who are excellent btw, although they did it on their new equipment, they said it did not need to be done as there is no rear adjustment. So thumbs down to Halfords Cannock, but then i think it was just down to the experience level of the mechanic who was put on the job, still you live and learn...........

 

[joey]

its all about the mechanic regardless of the company, I got a good feeling about the guys at halfrods in guildford and was proved right, they worked with me to get her through, and didn't have to, it was right at the end of the day and valentines day to boot and they all left 20 mins late as a result..

they probably got a bashing from their respective mrs's for that!

Gaz I have regular business in swindon I will drop you a PM the next time i'm due over that way..

cheers

joe

p.s thought these for my new thermostat and water pump

http://www.eurocarparts.com/ecp/c/BMW_Z3_1.9_1997/p/car-parts/car-cooling-parts-and-car-
heating/

http://www.eurocarparts.com/ecp/c/B...3b3463f10d5a9e84d4b9ec9ba7ae97a3a44ab6&000366

 

[GazHyde]

Gaz I have regular business in swindon I will drop you a PM the next time i'm due over that way..

The kettles always on

 

[joey]

excellent..

 

[zedonist]

valentines day to boot

Now you know why they helped you out, you were their excuse for not getting flowers due to working over that the florists were closed

 

[zedonist]

Or try these:

http://www.ebay.co.uk/itm/Bmw-3-Ser...MW|Cars+Type:1.9|Model:Z3&hash=item485c1a715d

http://www.ebay.co.uk/itm/BMW-3-Ser...MW|Cars+Type:1.9|Model:Z3&hash=item5d40fd93a7

 

[FRANKIE]

so gentlemen, this is an account of the day...

went to down to the local Halfords for the MOT test and it initially failed on seat bushings (never knew it could fail on this) but I told the guy to put the seats all the way back and this passed it ,they also replaced a number plate bulb...


the shocker was the emissions were all double what the should have been..I had about 30 mins earlier out a bottle of STP injector cleaner in but didn't have a chance to "open her up"....maybe some crap got dislodged and blocked an injector...really not sure..if felt fine though...

the chaps at Halfords suggested a "spirited run" down the A3 so thats exactly what I did...

so we did the gas test again and it passed by the skin of its teeth..phew!

so my question is where do I look first to deal with this issue?

my initial thoughts were

1 )cat two years old, but suspect a cheap one..

2) mixture..running rich MAF? or any suggestions would appreciated.

3) poor ignition, plugs? leads?

4) air filter..although this was new 4k ago so although i'm not ruling it out its unlikely..

5) oil contaminated by fuel?..


they did all say though otherwise a lovely clean car..

aceman need to order some bushings from you! have been delaying that TBH it looks like a pain of a job..

cheers

joe

When having to go through emissions testing here, its common practice to change the air filter. Some people remove it altogether until they finish the testing and replace it when they go back on the highway. A high HC (hydrocarbon) reading is most often the result of faulty vacuum hoses or lines. Giving a hot run down the highway helps blow out any carbon deposits. If you've ever replaced a head gasket yourself, you can look at the gasket to find the break, however most mechanics look at the cylinders to see which one is the cleanest. The break in the gasket allows the coolant water to seep into the cylinder. This water turns to steam and 'steam cleans' the cylinder and valves. As a result, some mechanics, on cars that have a high carbon buildup, get the engine running at operating temps, then rev it high and spray a bit of water into the intake manifold or throttle body to produce the same cleaning effect. This can have a good cleaning effect but you can also wreak your engine if you don't know what you're doing. Very dangerous if not done right. Frankie