Emissions advice - MOT failure
Emissions advice - MOT failure
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Eagle-220

Original Poster:

2 posts

74 months

Wednesday 29th January 2020
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Ibiza 1.4 tsi fr 10 plate

Before mot it had new spark plugs, ignition coils, fresh oil change and filter, clean air filter, had both oxygen sensors changed not that long ago.

I’m guessing from the high HC that the car is running rich, unsure on what to change/check next. Only things i can think of to replace would be engine coolant sensor and fuel filter.

I’m getting the cat checked tomorrow as well

Any help would be great


GreenV8S

30,999 posts

307 months

Wednesday 29th January 2020
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It does look massively rich. I think it would be worth getting the ECU checked for any fault codes and also any adaptive settings leading to enrichment. I don't know whether the coolant temp gauge is fed from the ECU on that car, but if it uses a separate sender it's possible that the ECU is getting a faulty temp reading which has lead to cold start enrichment.

I don't know how the fuel pressure is regulated on that car, but if it uses a vacuum referenced fuel pressure regulator then check that the vac reference line hasn't become detached or got a leak. Excessive fuel pressure is another possible explanation.

Eagle-220

Original Poster:

2 posts

74 months

Wednesday 29th January 2020
quotequote all
I’ve had the ECU checked for any stored or pending faults and there wasn’t any showing, would resetting the ECU help to clear any adaptive settings? Or is that just a load of crap...

I’ll check the lines, is there any way to check the fuel pressure without a pressure guage?

stevieturbo

17,965 posts

270 months

Wednesday 29th January 2020
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From the CO, it is clear it is massively rich. Some proper diagnostic work needs done, and seeing if any live sensor readings etc are amiss.
Or if the lambda sensors are even doing anything.

Why were both sensors changed in the first place ? and what were emissions readings before and after that ?

Welshbeef

49,633 posts

221 months

Wednesday 29th January 2020
quotequote all
Have you used the injector cleaner that you pour into the fuel tank? You might have clogged injector or injectors that rather than spray the fuel drip it in.

You might have a coked up engine - again fuel tank Additive can break it down OR a full on decoke without stripping the engine is possible too.

Do you use one in 4 tanks super unleaded 98/99 Ron vs 95?

Also how’s the car driven lots of short trips engine barely up to operating temps? Take it out on a long long drive make sure the gearbox and engine go through many heat cycles. Give the engine a full work out use high revs for prolonged periods of time get that engine really hot.