I bought a 2000 Skoda Fabia 1.4 16v (engine code AUB the 100bhp model)

After driving it a little while engine management light came on, took it back to the dealer we found it was giving the error P0402 Flow too high, they then bought a brand new EGR valve and fitted it for me (for free )

However then when i was driving it home the light came on again! took it back down to the dealer and this time it was giving the error P0401 Flow too low.

The mechanic thinks the P0401 could be caused by a faulty O2 sensor in the CAT but I cant see how this would effect it...

I have read some of threads concerning the EGR valve on the forums but i cant make much sense of it all as im not the most experienced with cars :/

So what could be causing this fault??

Edited 29 October, 201114 yr by Taylor93

Hi mate, i had the same problem and it occured after trying to clean the MAF sensor ( i made it worse :( ) Best bet is either to clean that or see if you can test a new one on it and see how that goes

Right after the brand new EGR valve was put in, the error came back, so we took it out, cleaned it up, made sure everything was fine, put it back in, drove fine for 25 miles and then ping! the light come back on, now with both error P0401 EGR flow too low and P0171 Fuel something too lean!

what on earth is causing it???

Hi mate, i had the same problem and it occured after trying to clean the MAF sensor ( i made it worse :( ) Best bet is either to clean that or see if you can test a new one on it and see how that goes

He doesn't have a MAF sensor because it's a 1.4 16V petrol!

OP if you disconnected the EGR valve to clean it you will need to get it re-adapted before the CEL will go out.

I drive around with the CEL permanently on because of this, the car drives fine so I just ignore it.

Edited 4 November, 201114 yr by sepulchrave

oh yea we clear the errors, but they keep re occuring!! despite all attempts to find out whats causing it

Clear codes. Switch on ignition for 10 seconds but don't start engine, switch off ignition and remove key. Then start car.

If that fails, have someone with vagcom/VCDS do the EGR adaption.

moggy after the code has been cleared it doesnt come back on for about 20 miles or so of driving, so why would leaving the ignition on for 10 seconds fix it?

Take the throttle valve off. Under it in the manifold is a small pipe sticking upwards with a cap on it. The sides of the cap should be clear, usually they are blocked with carbon, this leads to the EGR fault. Poke a small screw driver into the holes and wiggle it about to clear the carbon. Refit the throttle valve and adapt the EGR and throttle body, this should sort the problem. However check your software version of the engine ECU, if it's below 7000 then it needs the latest flash update as well.

thanks for the reply Tech1e, one issue is i have no idea on how to do that... :/

Do you have VCDS?

That can check the software version but for an update you need to go to a dealer.

It's an added cost but you probably didn't need to replace the EGR valve if the port is blocked, sometimes a dealer is expensive but sometimes half an hours labour from someone who knows the cars is better than replacing random parts hoping for a fix.

Like techie has said, it will be the pipes to the EGR, same as you bought, bought a 16v 1.4, light came on, garage first tried to clean EGR, came back on after 20 miles, back in and new valve, lasted 15 mile, back in again and this time they took all the pipes off and cleaned them up, hey presto, 700 odd miles later and no light anymore, from memory my code was the 1401, EGR valve, flow too low. Bought one of those cheap scanner/clearers from ebay to double check it myself as had never used the garage before but they were good to their word, just a shame it took 3 trips which was 200 odd miles in total