I have a new van to me, a FIAT scudo, and recently the engine management light came on and “ANTI POLLUTION FAULT” came on on the LCD screen. I plugged in my basic code reader and it listed two error codes. P0100 “MAF circuit malfunction” and P3008. This brings up nothing on google for FIAT but on a VW it brings up “Camshaft position (CMP) sensor – signal limit exceeded”, this FIAT has bosch fuel system which I think VW frequently have which to me would raise the chances that this is the same fault code? I’m guessing signal limit exceeded refers to the rate at which the camshaft signal is coming in? I would expect a camshaft sensor to be a optical or magnetic quadrature encoder. Perhaps unrelated but when cold it is easy to stall and requires more than usual revs. No smoke. No limp home mode.

I removed the MAF and it looks new and clean as if it has been relatively recently replaced. While I was there I also opened up the air filter to give it a blow though and it was missing. Do you think this may have been left out on purpose? The MAF would sense more air and cut back the fuel but I can’t see how that would help with anything?

My initial thoughts when the the “ANTI POLLUTION FAULT” text came up where ERG or DPF. Googling suggests DPF but how would this though up a MAF error? Surely a blocked DPF would result in too much back pressure on the exhaust side but that can’t effect the suction side can it?

Anyone have any thoughts. Off to by a air filter tomorrow.

I’m guessing signal limit exceeded refers to the rate at which the camshaft signal is coming in?

ECUs are quite sensitive about the signal coming from the crank sensor – not what the sensor is sensing but the quality of the signal the sensor is sending. When the sensor fails (or if the new sensor you buy isn’t up to snuff) then the ECU gets upperty. Its probably not that the sensor is reading a higher or lower RPM than it should be, more the quality of power/voltage/signal from the sensor isn’t up to snuff.

Aftermarket sensors can be more out-out-of range, new, than a borked OEM one

Is the Fiat electronics the same system as the Peugeot Expert it shares bodies with?

If so it could be anything really as it’s pretty common knowledge on Peugeot that “Anti Polution System Fault” Is just the code for matey got bored typing codes at this stage and used the same one for everything!

Maccruiskeen – Member
Thanks for the info was not swear of that.

Blazon saddles
I think they are both made in the same factory so I would guess so. I suspect you’re correct re the lazy code.

Mechanic mate suggest the DPF but how would that effect the MAF sensor?

Running without an air filter! Prob goosed your maf. They don’t like water or dirt at all. Goosed maf means dirty burn and more soot to block dpf. Maybe?
Think the cam shaft sensor only works on start up. After that the crank times the engine. If your engine start an fires, cam sensor is prob ok.

Sorry, in my tired and emotional state last night in confuse cam sensor for crank sensor. It’s the crank sensor I’ve had the issue of the replacement being more problematic than the one that was removed.

I doubt it’s camshaft error – codes are unlikely to be the same across different manufacturers I reckon. Anyway if your camshaft position sensor goes it will run but it won’t start when warm – or it’ll take 10 mins of cranking.

Could still be MAF – they are delicate. There are ways to verify the MAF I think on VCDS by monitoring various values and comparing them – there might be on your car too.

Anti pollution faults are more likely to be associated with the EGR valve I would of thought. How many miles on engine. Hopefully it’s not the DPF. Take the EGR valve off and check its not stuck. Don’t be tempted to take it out or bypass it, it’s there for a reason, to cool the inlet charge. Many people do this and it can hammer the turbo over time.

More good info thanks. Had a chance to have
More of a look. There appears to be no DPF, its early 2007 so I guess just before. Good point re damage MAF. Fitted a air filter. Lucky I took it off to have a look really.

I’ll try and take a look at the egr. That was my second thought as I drove along and it first came on. I’m going to clear the code and see if they reoccur.

Egr and maf can give the same error codes as they both relate to air flow.

Check all your vac lines and check the egr for sticking.

Where you based?

Thanks for that info. EGR is the next step.

Based Hampshire / Dorset boarder.