Faulty anti pollution warning light

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RPWC
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Re: Faulty anti pollution warning light

Post by RPWC »

Light is on again. Is. Air intake not same as maf? Funny how light and smoke disappeared after maf was cleaned.

RPWC
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Re: Faulty anti pollution warning light

Post by RPWC »

New maf fitted, no difference at all, so it is going back to the diesel specialist that cleaned the injectors last week, for further checks and testing.

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GiveMeABreak
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Re: Faulty anti pollution warning light

Post by GiveMeABreak »

You say it’s white smoke at startup? Does the smoke smell oily? If it doesn’t then it’s probably steam. If steam then possibly head gasket or valve stem seals. Head gasket leaks would be constant while driving, but the valve stem seals would be mostly at start up. But then again it may just be faulty glow plugs that can also cause it.

There’s just no way to accurately remote diagnose this Rich.

Fabio
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Re: Faulty anti pollution warning light

Post by Fabio »

Hi

I bought my Citroen C5 2.0 HPi nearly one month ago and since then I am having this Anti pollution warning light. It comes and goes but I don't feel any difference on the car's performance. I am thinking in take it to Citroen's repair shop to diagnose that.

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GiveMeABreak
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Re: Faulty anti pollution warning light

Post by GiveMeABreak »

But you say yours is an HPi - that's petrol Fabio unless you mean HDi? Rich has a Diesel and the Anti Pollution fault will be completely different.

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xantia_v6
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Re: Faulty anti pollution warning light

Post by xantia_v6 »

Isn't white smoke at start-up usually a symptom of a dead glow plug?

RPWC
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Re: Faulty anti pollution warning light

Post by RPWC »

Well I phoned the company that cleaned the injectors, as they told me to get bsck to them if I had any further trouble or queries, and the van is going back for further tests next Tuesday. Stopping with them Monday night,so they can check the smoke first thing Tuesday.

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Re: Faulty anti pollution warning light

Post by RPWC »

Not as much smoke on cold start this morning, only a little wisp on idle, have it a few revs and still a bit, but not as much as yesterday. Smells just like normal exhaust smoke to me, no oily or coolant smell. Guess I will just have to wait and see what happens next week, updates will follow.

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Re: Faulty anti pollution warning light

Post by RPWC »

There is a horrible smell of fumes around the van, not normal diesel smell, but more like a stale exhaust smell. Just wondering if it’s cat related? Had a diag done yesterday which showed faulty Maf open circuit on no4 injector, and open circuit on air intake temp sensor. He said these could be prior to getting the injector work done. He has cleared the codes so will see what happens on Tuesday.

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GiveMeABreak
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Re: Faulty anti pollution warning light

Post by GiveMeABreak »

Interesting - I would of expected them to clear the codes down after the original work - and if you are still getting smoke / fuel smells then something isn't right.

Did they do a leak back test? If there is too much fuel being returned, the injection pump won't be able to maintain pressure to operate the system correctly and that can also cause limp mode, idle running - especially at startup and low engine revs.

Did we we ever get the codes? I think we asked for them a while back - but you mentioned it hadn't been checked at the time. A P1211 for example would indicate a fuel pressure problem as an example.

RPWC
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Re: Faulty anti pollution warning light

Post by RPWC »

No codes were actually given to me Marc just the results. I had this smell or similar with my last Dispatch , the 1.9 n/asp XUD engine, turned out to be.blocked cat . This one has cat straight off manifold so cant disconnect to test. Is the 2.0 a less troublesome engine cos Im seriously considering getting rid of this. Its an absolute nightmare. Since purchase I have had blue smoke from exhaust dead battery faulty fuse box white smoke e m l twice, leaking injector and this foul fume type smell. All this in only 5 months and 3000 miles. Had I only paid 1k for the vehicle, it would be reasonable to have to do work or running repairs, but not at 5k. If the test next week comes up trumps then it will be returned to dealer for fix under consumer rights act 2015

MikeT
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Re: Faulty anti pollution warning light

Post by MikeT »

RPWC wrote:
07 Sep 2018, 08:34
Had a diag done yesterday which showed faulty Maf open circuit on no4 injector, and open circuit on air intake temp sensor. He said these could be prior to getting the injector work done.
This is what I was getting at earlier. While the MAF houses both an airflow and temperature sensor, pre-boost. (I understand this was first cleaned and then later replaced).
Post-boost, there's another air intake temperature sensor (I call IAT) and a pressure sensor (MAP). It could be worth cleaning both with contact cleaner and checking their connections are firmly in place.

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Re: Faulty anti pollution warning light

Post by RPWC »

Where are these connectors and sensors Mike? There is nothing after MAf,, just been taking to a mate who is fairly clued up on engines, and he said this white smoke is fairly common place on vehicles that have had cheap supermarket diesel in the tank. Apparently after the really hard winter we had earlier this year, the diesel can freeze and turn into balls of wax like substance, which causes the smoke, until engine is warm. Apparently using shell v power I’d BPultimate,both of which contain detergents,and burn hotter, will clear it in a couple of weeks. Failing that he said to remove tank,and give it a good rinse out with clean fuel, refit and fill with v power or ultimate.
He has an old Transit Connect, and when he bought it,it was smoking terribly, as previous owners had run it on cheap fuel, red diesel and just about anything they could find. He changed the fuel filter,and started running it on v power, now it’s fine. Worth a try I guess, costs a bit more, but lasts a bit longer. I put a small amount of it in today,and it did seem to run quieter,and that horrible stench wasn’t as strong either.

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Re: Faulty anti pollution warning light

Post by MikeT »

It's pure guesswork Rich, as I don't know what the Diagbox/Lexia fault codes are (which will state specific sensors), nor what engine variant you have but if it helps, post-boost sensors may be found downstream of the turbo, in the air intake.

As for fuel contamination, yes, if it's bad drain and clean the tank and flush the lines through if possible. Otherwise just brim it with premium fuel as often as you can afford and/or use a quality fuel additive to see if things improve.

Some might say cheap supermarket fuel is perfectly fine though I'm not one of them and will avoid it like the plague, whenever possible.
Though I've never known it to be blamed for causing white smoke on cold starts. That's usually down to failed glowplugs (though less so with HDI engine) or low compression or just steam (water/condensation).

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Re: Faulty anti pollution warning light

Post by RPWC »

Well, I am not losing coolant or oil, there is no coolant in oil or vice versa,so I am ruling out HGF. I will report back after it has been to the diesel specialist. It’s getting dropped off on Monday evening, so they can check it out from cold on Tuesday. It does not lose any power during normal driving, although being the 1.6; it is underpowered anyway. It will still hit 90mph on a dual carriageway,with a slight downhill slope, other than that 70/80 is achievable no problem, it will also pull up gentle inclines in 4th gear, but what puzzles me most is this god awful stink from it, like exhaust fumes, but not normal exhaust fumes. It’s difficult to describe.