The engine management light on our Fabia 1.2 Classic (AZQ engine) has come on permanently and using a Gendan VAGScanner fault code reader (usual disclaimer) I've found the fault code is P1440/17848. The car has 122k miles on the clock. I've checked the Ross Tech site and they don't have a diagnosis procedure for this fault code.

Having read all the posts on Fabia 1 Pierburg EGR valves I have assumed the EGR valve is 'cooked' and will need replacing with a need one. Before committing to purchase a new one I've bought some gaskets and will remove EGR valve this weekend for a strip down to see if I can clean the internals, try to diagnose the cause of the fault code and get it working - even if this will be a temporary fix!!

Is there any published procedure for checking EGR valves?

I'm led to believe that if I disconnect the EGR valve from the engine harness it need zeroing in using a VAGCOM or similar computer system to do this - I wondering if I remove the earth lead from the battery before starting this work the ECU should reset to a default state and re-start its learning mode when I finally reconnect the battery in-order to check out the engine systems - is this correct?

Has anyone got any other comments/recommendations?

Thanks in advance

Jamiel

This should be reasonably easy to check out as long as you have a multimeter (or can borrow one).

The solenoid coil on these is between pins 1 and 5 according to some records I made when I replaced mine. I measured 8.3 Ohms between these pins on the new EGR. If you get a number somewhere around this value, the EGR itself may not be at fault. While you're at it with the meter, measure the resistance between pins 2&4, 2&6 and 4&6. I got 3.64KOhms, 3.87KOhms and 1.43KOhms respectively. If all these numbers come out in a similar ballpark, the position-feedback potentiometer is OK too.

All these measurements will be far easier with the valve off the car, but may be possible in-situ, not sure.

If that all checks out you have to suspect a wiring fault, particularly with the 12V or ground wires that go to pins 1 & 5.

As the EGR has no permanent live feed, and no internal 'intelligence', disconnecting it from the loom will not cause the ECU to get its knickers in a knot unless you switch the ignition on while it is disconnected.

There is an 'actuator diagnosis' procedure you can do with VCDS which would test the power side of the EGR function (by making it click open/closed a few times which you can hear/feel), but you could do this with a carefully applied external 12V if you have no ready access VCDS. I forget which pin is +12V and which ground out of 1 & 5, it may not matter, but see what wire colours go to those pins, that may be a giveaway. Can't check myself as the missus is out with the car. Pretty sure the pin numbers are labelled on the connector(s).

Wino

Thanks for the info - I have a multi meter so will check to see if my readings are similar to the ones you found. Its not clear on Ross Tech website but I'm wondering if VCDS lite does the actuator test you suggest otherwise may try using 12V assuming I can confirm the wire colours (I guess VW/Slokda used DIN/ISO standard colours!!!).

Did Pierburg improve their EGR valves further since your posts on this subject?

Thanks again

Can't say whether VCDS lite will do the actuator test, as the guy that helped me out had the £260 full version.

I'm not sure how much Pierburg would have changed the valve design/materials after problems occurred in this application. If you believe their service bulletin, the temperatures that the things have been exposed to were beyond what they were designed for, and the necessary changes were in ECU mapping. What is the four-digit code on your ECU's label, just below the "033" of the part number. I think that's the software version number that it was built with. Compare with what Pierburg say it should be as a minimum in that service bulletin. May be worth getting it updated at a dealership if it is a lower number, or at least checked to see what's in there. VCDS lite may do the latter for you?

Hi Wino

Our Skodas ECU four digit code is 4672 (if I've read the label correctly) which is below the Pierburg range of 5323 to 5329. This assumes that if a software update had been done by a dealer they'd bothered to change the label - though I suspect that the latest ECU code would be in the memory of the ECU. I cant check this unless I go to a dealer or use VCDS - my simple Gendan fault code reader doesn't give this information.

A bit more research is needed on VCDS lite before I purchase a lead as Ross Tech and Gendan both state VCDS lite and a simple EOBD 16 pin to USB lead is suitable for VW/Skoda models up to 2003. I assume CAN protocol was implemented in 2004 which needs a different and more expensive lead - unless anyone knows different!!

My EGR strip down has been officially delayed as my wife wants the car this weekend to visit the in laws so will report on my findings next week.

Thanks again for your help,

Jamiel