D5254T (to 2002, Audi) egr fault

[BillB]

Hi, I currently have an intermittent engine light on my V70 Tdi classic (Audi). The fault code refers to "egr flow faulty" so I've checked the pipes to the egr controller and they are clear. Has anyone had this issue and solved it? I'm thinking it's either an intermittent egr controller or partially blocked egr valve. Any suggestions as to what to look for? Regards.

[keithC70]

On mine I've completely disconnected the egr valve and had no warning lights.

It just seems crazy to me to go to the trouble of cooling the intake through your intercooler to make it extra dense - and more efficient, and then injecting hot exhaust gas into it! Madness!

I know the idea is to reduce nitrous emissions but really! They'll have us driving with the brakes on next!

[outnumbered]

Originally Posted by BillB

Hi, I currently have an intermittent engine light on my V70 Tdi classic (Audi). The fault code refers to "egr flow faulty" so I've checked the pipes to the egr controller and they are clear. Has anyone had this issue and solved it? I'm thinking it's either an intermittent egr controller or partially blocked egr valve. Any suggestions as to what to look for? Regards.

have a look at this it may help you.
mike

[altajeli]

[QUOTE=keithC70;837078]On mine I've completely disconnected the egr valve and had no warning lights.

Have you noticed any MPG/performance difference? I am seriously considering blanking mine off, v70 d5 163bhp

[outnumbered]

[QUOTE=altajeli;837260]

Originally Posted by keithC70

On mine I've completely disconnected the egr valve and had no warning lights.

Have you noticed any MPG/performance difference? I am seriously considering blanking mine off, v70 d5 163bhp

i would be carefull depending on what year it is it may thro a wobler.
mike

[BillB]

keith
I'm surprised you've had no fault light on. Maybe the amount of exhaust gas entering the inlet is insignificant compared to the volume of cooled air i.e. so it doesn't heat it much? Regards.

[outnumbered]

there is another thread ongoing here http://www.volvoforums.org.uk/showthread.php?t=115824 i have spoken to steve on the phone and he has a code logged, also one of the pipes is not attatched to anything this we presume is causing the fault its the pipe that goes undwer the air box. if i read that fault correctly you must have complete vacum so that it will not throw up a fault. if you wish to disconect the egr i would have thought that the egr pipe would have to be blocked .
mike

[BillB]

Mike, I do have the 0038 code indicating egr flow too high or too low. I didn't intend to disconnect it. Haven't looked inside the egr valve or controller yet so hoping one of them will look suspect. The CEL is coming on and off so I'm presuming the egr flow is going out of tolerance intermittently. I do have VADIS btw (but not a VCT2000 I'm afraid). Regards.

[keithC70]

Altajeli

Doing this on my tdi hasn't altered mpg but it's definitely producing less smoke on hard acceleration.

I had an S80 D5 SE Auto last year and I was so shocked at the deposits in the plenum/mixer tube that I blanked that one off too using a bit of an aluminium coke can that I found in the front garden one morning! I didn't get any warning lights or fault codes (I have the BSR ppc reader).

I don't think there was any measurable change in performance or mpg but I drive relatively slowly and generally don't accelerate hard and was getting 42 round town and 48 on a motorway trip - astonishing for a car of that weight.

I think the main difference would be that there would be fewer deposits in the intake system in the future.

[BillB]

I've now checked the egr controller electrically and it seems OK. Also there is a vacuum at the pipe connecting to the egr valve but only slight to the feel - I don't have a vacuum gauge so does anyone know how much vacuum should be felt? I can't see how you disassemble the egr valve - any suggestions? I also don't see how the vacuum is sensed by the ECU so how does it know of a vacuum fault? Regards.