Engine Warning light coming

[TLondon]

I’ve got a 57plate MK5.

In May I had my aircon regassed and air conditioning sensor put in.

Driving away the next day engine light came on for 24 hours, nooked into the local garage but the next day went away.

It has just come back after filling up the full tank with petrol - the engine has not been run any differant and I have secured the engine cap correctly - any ideas?

There is no change at all in performance.

[TLondon]

Also can anyone recommend a good value VW specialist in south east london/kent as my Garage always seem to be scratching threir head - on the last air cable fault I actually got the answer from this forum on their third attempt and it was a £100 job.

[LC5F]

the CEL on our cars is fickle - it could be anything or nothing - sadly this does lead to humour from folks who have not seen the light (pun intended):


Being serious, to keep yourself sane I suggest getting some sort of code reader, cheap Bluetooth OBD readers are less than £10 and there are free apps to put on a phone and it will cover you for all the serious stuff.

[TheBALDpuma]

I agree with the above that there are a ton of things it could be.

To add one to the pile that I've just had similar to you.... EML but no poor running etc.  It was the charcoal canister. Easiest fix ever.

[TLondon]

This gives me hope, thanks for the response.

Is there anyone in the South East that anyone can recommend to take a look? My garage last time this happened was three trips and two “fixes” before I got the info from here. As it stands its going in their Wednesday.

[TLondon]

the CEL on our cars is fickle - it could be anything or nothing - sadly this does lead to humour from folks who have not seen the light (pun intended):


Being serious, to keep yourself sane I suggest getting some sort of code reader, cheap Bluetooth OBD readers are less than £10 and there are free apps to put on a phone and it will cover you for all the serious stuff.

I have just ordered one from Amazon coming tommorow:

“ Edasion OBD2 Bluetooth 4.0 Diagnostic Scanner Code Reader for iPhone iOS Android iPad PC, Car Auto Odb2 OBD II Diagnostic”

[pudding]

CELs generally only come on for the mandatory emissions stuff, as decreed by Brussels sprouts, which can put people on the right diagnosis path:

Primary & secondary O2
Catalyst efficiency
Evap circuit
VVT (for EGR reasons)
Misfires once a threshold has been met

Other stuff generally just gets stored as a fault code with no CEL, or more commonly.....the engine will run like a bag of hammered sh1t with absolutely no codes 

[OllieVRS]

Sometimes brimming the tank can cause a CEL as the fuel can splash into the charcoal canister or something along those lines.

I got a P0441 "Evaporative Emission Control System Incorrect Purge Flow" which could have been the charcoal canister, the N80 purge evap regulator or simply the petrol cap being loose. I started off with the cheapest item, replacing my petrol cap with a FEBI Bilstein one solved the issue, but even now I still try to stop a litre or two before the pump clicks out of habit. My car was also running fine with the CEL.

But do definitely scan it before throwing money at it.

As @Pudding said though, the TFSIs sometimes don't throw CELs when they really should. I blew off one of my boost pipes when I was hammering it, massive thud from the engine, lost nearly all power, and nothing on the dash

[TLondon]

Thanks all some good food for thought - I’ll share the codes tommorow if anyone can be kind enough to comment on those.

Cheers

[pudding]

As @Pudding said though, the TFSIs sometimes don't throw CELs when they really should. I blew off one of my boost pipes when I was hammering it, massive thud from the engine, lost nearly all power, and nothing on the dash

Yep! One time when I didn't clip the boost pipe into the turbo properly, and it blew off, zero fault codes     It would just cut out instantly at any speed above idle, but the ECU was like, nope, nothing to see here, carry on!

[TLondon]

i’ve got the reader and using Car Scanner - can anyone assist on where to go? Loads of information available but nothing obvious (to me anyway).Or recommend a ios software.

[TLondon]

One error came up - looks like something to do with the fuel/refuelling - any ideas?


https://www.volkswagenforum.co.uk/threads/p0441-recap-system-incorrect-purge-flow.21358/

[TheBALDpuma]

That's either evap canister (the charcoal canister I mentioned), valve, fuel filter cap not sealing ita split in the evap pipe network. I think.

[GVK]

I think a large majority of mk5s have that code when scanned.

My old ed 30 had it the whole time I owned the car but it only put the CEL on once every few months

[TLondon]

I’m tempted to get an OEM charcol canistor off Ebay and fit it myself. Looking through the forums looks pretty straight forward. How much would a garage charge for the N80 replacement roughly?