My Escort (R reg 1.8 16v Ghia X hatch) has failed its MoT test on emissions. The readings varied a lot, and the tester tried every possible way to get them down to a pass figure but with no joy. The end results were:
Fast Idle Test:
CO (<0.3%) 0.003%
HC (<200ppm) 10ppm
lambda (0.97-1.03) 1.202
Second Fast Idle Test:
CO 0.006%
HC 3ppm
lambda 1.273
Natural Idle Test:
CO (<0.5%) 0.219%
The Lambda figures are too high, ie there is too much oxygen left in the exhaust after combustion has taken place - in other words the engine is running lean. This is borne out by a slightly woofly idle and a hesitation on light throttle openings.
The MoT tester pointed out a vacuum hose underneath the back of the engine that could be split, but today I found that the same hose was actually not connected to its termination on the back of the inlet manifold. After taking the hose off the car and cleaning it anyway, it seemed to be sound so I refitted it. The car ran much better all the way back to the test centre, whereupon it promtly failed again with much the same figures.
Any ideas?
Last edited by: VxFan on Tue 18 May 10 at 10:32
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Check for air leaks.
The pipe that dropped off did so for a reason - has the end begun to split? I would put a new length of pipe on.
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The CO and HC readings are well within spec.A high lambda reading on this car seems to indicate a leak in the exhaust system (sucking in air).Check the joints and seams for any cracks or pinholes from the lambda sensor area to the rear silencer box.An unsteady idle could be caused by a faulty pcv valve .It is situated behind exhaust manifold,by #4 cylinder .Also check the rubber elbow attached to it.hth
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Thanks, I will do all of that in the morning when it's cooled down and I can safely reach round it. The car has had new middle and back sections of exhaust about 8 weeks ago so I will inspect the joins very carefully.
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Different engine but we had a 1.6 Zetec Escort which failed on the same thing. The garage then just gave us a dodgy MOT instead (they used another car). My uncle then had a look at it and came to the conclusion that some of the valves were sticking.
I don't know what the readings were and it may be a completly different problem but those Zetec engines due tend to suffer from sticky valves if the wrong oil has been used.
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>>The CO and HC readings are well within spec.
While checking the exhaust is always a good thing to do, it will have been checked itself as part of the MOT.
The CO and HC figures are consistent with a weak mixture - the excess oxygen available being used in the cat to oxidise the HC and CO to CO2 and water.
The PCV valve is a very good item to check, as these do tend to be neglected on older Fords. I used to renew them as a matter of course at large services.
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>> PCV valve
Looking at the Haynes manual, that's where one end of the vacuum hose in question appears to go. Lots more fun to be had in the morning, I can see it.
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>> Zetec engines due tend to suffer from sticky valves if the wrong oil has been used
I'd heard of that one myself - apparently its only a problem in the UK because we all pootle around under 3,000rpm, while the continentals wring it out to the red line in every gear! In any case, I've been changing the oil regularly and using 5w30 synthetic with "Ford A rated - suitable for Zetec petrol engines" on the can. Should I take another car for the emissions test then??
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What I used to do to check for induction air leaks was to spray some carb cleaner around a suspect area
and see if the engine RPM was affected, which would normally indicate a leaking inlet manifold gasket,
even WD40 would have some effect if it was thus.
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Isn't WD40 harmful to catalytic converters?
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There was a predilection in the UK for putting 20w/50 in every engine and not following the makers' recommendations.Most crankcase ventilation systems can do with a thorough clean,not just of the valve but also of every filter and orifice;a new PCV valve assy. is not expensive.
Last edited by: jc2 on Tue 18 May 10 at 09:27
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>>>Isn't WD40 harmful to catalytic converters?<<<
You could be right, I don't know ... how's about fuel system cleaners and the like (Forte) do they kill cats?
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>>how's about fuel system cleaners and the like (Forte) do they kill cats?
I suppose they've got to be formulated to be benign to cats.
IIRC there was quite a discussion around the time petrol contaminated with silicon/silicone was damaging lambda sensors. Perhaps it was the sensors WD40 could damage.
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>>I suppose they've got to be formulated to be benign to cats.
Perhaps it was the sensors WD40 could damage.<<
Cheer's tommo ~ point taken ... if I see any cat's in my garden I'm gonna spray them with WD40 :)
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There is NO silicon in WD40(read the tin);the two main chemicals that kill catalytic convertors are lead and sulphur.
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>>if I see any cat's in my garden I'm gonna spray them with WD40 :)
No need. If you want to get rid of them then you need to 'engineer' a coolant leak somewhere so it forms a pool for cats to drink from. It's lethal to their livers (I'll have to start drinking something else).
A vet informed me many 'local cats being poisoned' stories can be attributed to leaking cooling systems.
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>>A vet informed me many 'local cats being poisoned' stories can be attributed to leaking cooling systems.<<
At least the poor little blighters didn't freeze to death then.
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Well, it finally passed its MoT today!
Only by having the relevant vacuum hose jubilee clipped at either end (nowhere seems to sell vacuum hose any more, I tried the Ford main dealer, Halfords, a big industrial estate motor factor and a little old school spares place) and then by having the engine revved to a full 6,500rpm and held there for 30 seconds. There was a definite smell of engine death in the air for a while afterwards...
I think it's doubled in value now it's got a full ticket.
Last edited by: Dave_TD {P} on Sat 22 May 10 at 23:55
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Another 12 months of life then!
Amazing not to be able to buy any vacuum hose, I suppose you have to point to the relevant part on the PC screen in the Ford parts dept. that is if they keep parts for 13 year old motors...
Was there a problem with the PCV valve? I remember looking at the one on my Mondeo and thinking I didn't really want to try to remove it if it wasn't broken! Not easy to get to, but Number Cruncher has obviously changed a few. Hope my Focus hasn't got one....
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>> and then by having the engine revved to a full 6,500rpm and held there for 30 seconds<<
I missed this post on Sat. for some reason Dave - why was the critter revved at 6.5k then?
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I assume it was to clear some gunk out of the engine - I occasionally take it up to 5,000 on the odd slip road but I'm usually expecting something to go bang when I boot it that hard. This was absolutely full-bore, pistons tapping on the inside of the bonnet, red-line revving - I was quite pleased it survived that, let alone passed the emissions test!
>> point to the relevant part on the PC screen in the Ford parts dept
Done that, found out that it's only £3.53 but no Ford dealer in the country stocks them. The parts dept guy suggested buying a length from a motor factor.
I don't know if there's a problem with the PCV valve, as percy says I don't fancy taking it off to find out! (it's between the exhaust manifold and the cylinder block, and the manifold has a special way of being located on re-fitment just to make it doubly awkward).
Last edited by: Dave_TD {P} on Tue 25 May 10 at 11:25
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>>and then by having the engine revved to a full 6,500rpm and held there for 30 seconds<<
That amounts to GBH in my books ... its belt drive I take it (jeez!)
Bad enough being present for a diesel smoke test on my cared for £28k Merc.
Re: the PCV valve, I've actually seen injuns whereby the owners have stripped & rebuilt the critters,
all for the want of a new PCV valve or a blocked breather.
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Yes, it's belt drive (possibly overdue as well)*. On my limited budget I can't justify taking too many bits apart in the interests of longevity - I was glad to get it through this year so with a fair wind it'll keep going for another 12 months. I change the oil and filter every 10k miles, the antifreeze every 2 years and tyres, brakes, bulbs as required; that's more than a lot of motorists ever do.
*I bought the car on 80.5k miles at 11 years old, with history up to 58k / 8 years. Now on 108k at 13 years old, changed oil at 83k, 93k and 103k. Handbook says belt change interval is 100k miles / 10 years. Ford dealer says 80k miles. Haynes manual says 60k...
Last edited by: Dave_TD {P} on Tue 25 May 10 at 18:00
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I wouldn't leave that belt too long comrade Dave - if it goes it'll undo the benefit of regular oil changes.
From my experience with cam belts, its always prudent to err on the side of caution!
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Cost of belt change: ~£200.
Likely life expectancy of car (belt failure notwithstanding): 1 year.
Scrap value of car: ~£150.
Replacement car: £400.
Disposable income: ~£0.
If I can afford to get the belt changed I will, but I don't think it's going to get done any time soon :-(
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>>Cost of belt change: ~£200.<<
Jaysus! I used to do em for 25 notes on the ole Cortina's etc ... progress???
I'll say it b4 someone else does ~ "but today's cambelts are stronger & last a lot longer":)
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> I used to do em for 25 notes on the ole Cortina's etc
Whoa! How'd you support yourself on that kind of money!
Or were they really quick to do? As easy as a modern aux belt?
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>>Whoa! How'd you support yourself on that kind of money!<<
Ah, but ... I used to be a mobile tuner & I'd charge £30 for say a 'cooking' 4 pot,
I'd change the oil if they wanted = that's another fiver + the texas tea,
So what's that ... 5 + 30 = hang on,. I'll get me calculator,
The cam belts on the Ford OHC Pinto was a piece of gateaux really,
I'm no mechanic (as such) but I'd do the Rover 2.3/2.6, Vxhll's, Accord & the like.
Right, I've got me calculator and that little lot adds up to £60 inc. the belt fitting + parts,
if I did 4 of them a day that's about £240 a day which is better wonga than lorry driving which I did b4.
We're talking late 80's early 90's btw.
:-)
Last edited by: Dog on Thu 27 May 10 at 13:20
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>> about £240 a day which is better wonga than lorry driving
>> We're talking late 80's early 90's
I can remember paying £24 for a full tank of four-star in 1991, so £240 t/o a day ain't bad at all!
>> Cost of cambelt change: ~£200
Actually £170-something plus VAT at the Ford dealers, or two hours' labour at the local tyre & exhaust place plus £80-odd parts. Ebay have the belt plus tensioner for about £60 inc p&p but with no guarantees of quality.
Last edited by: Dave_TD {P} on Thu 27 May 10 at 22:40
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Pretty sure the kit is only about £85 from Ford. The problem with the early Zetec engines is they had plastic pulleys which drive the cambelt, these sometimes shatter throwing the belt off and damaging those valves.
My dad paid £156 to some old bloke who was dying of cancer to change the belt on his Escort. It took him 12 hours to do! My uncle recomended us to him but I think the bloke should have just said he was too ill to the job.
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The price of £170 from Ford was including fitting, Rattle. Which I was quite surprised at too!
It's not an early Zetec engine, it's a later Zetec-E (automatic cambelt tensioner, different valve guides to address the sticky valve issue*, more eco green gubbins).
*But I still use fully synthetic oil anyway.
Last edited by: Dave_TD {P} on Fri 28 May 10 at 01:42
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The Mk.III Cortina cambelt could take a whole 1/2 hr. to change if you took your time.Very little to remove from the front of engine,you could leave the radiator in and it tensioned itself(spring) and clear markings on c/shaft pulley,cam pulley and distributor.
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>>so £240 t/o a day ain't bad at all!<<
Nay, I didn't do belts & oil every day, only if the car was a non-starter due to belt failure,
or if ze customer particularly asked for it 2b done,
I'd much rather fiddle about with the contact breakers & the idling mixture screw :)
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Ford Escort - 97 1.8 failed MoT on emissions - high Lambda readi - Number_Cruncher
