Anti-Pollution Fault Again!

TroyO

TroyO

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Fellow Frogger
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Location
Perth, Western Australia
I was driving to work this morning with the engine light came on and the MFD displayed Anti-Pollution Fault again. This makes it the 5th time it has happened to this car in just over a 1 year period. They have already replace one of the oxygen sensors mid last year, and the last time it happened in December they updated the ECU software saying that should fix the problem.

The car never misses a beat, but the problem is very annoying nevertheless, since I have to go back to the dealer to get them to look at the problem.

:mad:

Troy.
 
Hi. Do you mix different brands of PULP. I've experienced the same problem before but I now only use the 98 RON Optimax. Different petrols from different oil refiners have their own unique formulation. My engine suffers a "hiccup" when they are mixed, even if they are all 98 RON. I haven't experienced any problems now when I used the Optimax. As much as possible I also fill up only from one station, the busiest one with fresh stock, I assume.
 
Juan M. said:
Hi. Do you mix different brands of PULP. I've experienced the same problem before but I now only use the 98 RON Optimax. Different petrols from different oil refiners have their own unique formulation. My engine suffers a "hiccup" when they are mixed, even if they are all 98 RON. I haven't experienced any problems now when I used the Optimax. As much as possible I also fill up only from one station, the busiest one with fresh stock, I assume.
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No I run the only 98 octane fuel we can get in Perth, BP Ultimate, I never use anything else.

What annoys me is that there does not seem to be a solution in sight. It's not so much of issue now as it is treated as a warranty issue. But if this continues out of warranty then it will start costing me for them to look at it.

Troy.
 
Troy mate, I've had simular anti-pollution fault problems also. Only twice in three years though. The first time was the O2 sensor and the second was an apparent false alarm (the dealer said that the coolant sensor had given a faulty reading to the computer) In both cases however the car drove in its usual manner and had no effect on its performance. Unlike many cars, the VTS is able to tell the driver ( instead of the mechanic using diognostics ) about any number of faults that "might" be potentionaly serious on it's computer display. In other cars the driver may never be aware that somthing is wrong until the car goes in for its regular service. Perhaps the VTS gives us too much info and that can be frustrating if its a false alarm. In the end you can forgive these annoyances because of the pleasure of driving such a great car. Also remember that Aussie fuel is poorly refined and does not meet with the standards that Europeans take for granted. This is a big problem for hi-tech euro motors.
 
got the same problems here with my 180. first time it was fuel. then yesterday it came on, lost power, engine stoped then came on again. this morning it still display the fault but after work when i got back in, the problem was gone. Perhaps it is something that is shared between both cars, sensors mabey?
 
Xsara VTS/ Pete said:
Unlike many cars, the VTS is able to tell the driver ( instead of the mechanic using diognostics ) about any number of faults that "might" be potentionaly serious on it's computer display.
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Unfortunately a lot of the faults fall under the General Protection Fault... I mean Antipollution Fault category.

This issue is problem something to do with tight sensor tolerances and variable fuel quality, combined with weather. It only happens during warmer months. I suppose I should be glad the car still runs properly. Still it would be nice to get to the bottom of the problem. Some PSA vehicles have the problem, while others don't.

Anyway the car is in next Wednesday, so I will find out what they have to say about the problem then.

Troy.
 
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I have mentioned this previously - it is believed that during the warmer months (high temperature + low air density) that whilst coasting the rapid closure of the throttle butterfly causes a air/fuel ratio anomolie at the oxygen sensor. This is compacted by aging sensors.

It is nothing to worry about unless it is associated with power loss (outside of the normal hot day performance), significantly erratic idle or surging.
 
Xsara VTS/ Pete said:
Troy mate, I'd be interested to hear what the dealer has to say. Keep in touch.

Cheers Pete
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Will do. It will be interesting to see if the fault is an anomalous reading on one of the oxygen sensors as XsaraVTS said (and has been before in my case), or whether it is something else.

Troy.
 
Aussie fuel isn't the only bad fuel out there, try American fuel, most gas stations in my town have 85, 87, and 89 octane, a few have 91, and they charge about 30-40% more then for it then they do for the 87 or 89, I know of ONE station in town (greater metro area where I live has about a million people) that carries 97 octane gas, at a cost of almost tripple the 87, and the 87 octate is usually a 90% petrol, 10% ethanol mix. My cx doesn't like the 85 or 89 that much, prefers the 87 when it is 10% ethanol (I guess the ethanol must burn differently somewhat) so that is what I run on.
 
Got the car back this arvo. The problem turned out to a be a software glitch. It was something along the lines of the ECU reporting a missing airpump. The only problem is that car doesn't have any air pump (I thought those things weren't being used for a long time). They have updated the ECU software, so hopefully that will fix it.

Troy.
 
DCTalkJCFreak said:
I know of ONE station in town (greater metro area where I live has about a million people) that carries 97 octane gas, at a cost of almost tripple the 87, and the 87 octate is usually a 90% petrol, 10% ethanol mix.
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And exactly how much do they charge per gallon for this rarified 97 stuff?

Good to see your car is behaving itself again, Troyo. As for the airpump, it's not something they use on the diesel to produce vacuum pressure or something like that (my poor knowledge of diesels coming to the fore...), by any chance?

Now where did you put that airpump you took off :nownow:
 
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SLC206 said:
Good to see your car is behaving itself again, Troyo. As for the airpump, it's not something they use on the diesel to produce vacuum pressure or something like that (my poor knowledge of diesels coming to the fore...), by any chance?
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I'm not sure. I always thought that it was part of the antipollution system on older cars in some markets. I remember that certain model Euro's had them for the American market.

SLC206 said:
Now where did you put that airpump you took off :nownow:
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I asked the factory to leave it off when they built the car. I was just thinking that the ECU was a bit slow, it took long enough time to realise it wasn't there. :crazy:

Troy.
 
SLC206 said:
As for the airpump, it's not something they use on the diesel to produce vacuum pressure or something like that (my poor knowledge of diesels coming to the fore...), by any chance?
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Or your poor knowledge of Petrol engines. :nownow:
Some cars used to pump air into the exhaust to either aid the completion of the combustion process or give a better exhaust gas reading when they test it during compliance. :tongue:
 
TroyO said:
Unfortunately a lot of the faults fall under the General Protection Fault... I mean Antipollution Fault category.

This issue is problem something to do with tight sensor tolerances Troy.
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Tighter than a ducks bum ! :( With so many sensors under this "anti-polution fault" read-out on our MFD, its no wonder it lights up more than a Xmas tree :nownow: These computer glitches are a real annoyance to VTS drivers, especially if they are all false alarms. Is this problem only isolated to Xsara or do other Citroens suffer from faulty read-outs?

Pete
 
Xsara VTS/ Pete said:
Tighter than a ducks bum ! :( With so many sensors under this "anti-polution fault" read-out on our MFD, its no wonder it lights up more than a Xmas tree :nownow: These computer glitches are a real annoyance to VTS drivers, especially if they are all false alarms. Is this problem only isolated to Xsara or do other Citroens suffer from faulty read-outs?

Pete
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Don't know about other Citroen's, but I have heard of some Pugs getting spurious Antipollution faults. The software update I had done in December to fix another anti pollution fault issue was also for Peugeots, mine was the first Citroen the workshop had done.

Troy.
 
TroyO said:
Don't know about other Citroen's, but I have heard of some Pugs getting spurious Antipollution faults. The software update I had done in December to fix another anti pollution fault issue was also for Peugeots, mine was the first Citroen the workshop had done.

Troy.
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Troy mate , thanks for the info. Next time this "fault" lights up I'll get the dealer to do a software upgrade and hopefully solve this erratic problem. Keep on enjoying your VTS and keep in touch.

Cheers Pete
 
TroyO said:
Don't know about other Citroen's, but I have heard of some Pugs getting spurious Antipollution faults. The software update I had done in December to fix another anti pollution fault issue was also for Peugeots, mine was the first Citroen the workshop had done. Troy.
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Always makes you wonder if the software is preventing accidental indications, or they are just turning the tollerance down so you don't get faults :)

- xTc -
 
XTC206 said:
Always makes you wonder if the software is preventing accidental indications, or they are just turning the tollerance down so you don't get faults :)
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I believe December's software update including remapping of sensor tolerances so you never know. :)

Troy.
 
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