DPF Warning Light A3 TDI 170

[Lanky76]

Hello all,

I have had the DPF / Engine management light appear 3 days ago now. I have been trying my hardest to clear using the method stated on these forums and in the user manual, this being drive above 2000rpm in either 4th or 5th gear for 15 minutes or more, in an attempt to clear. I thought never mind I will be going to the inlaws at the weekend and that will be a good run to clear out the cobwebs... The trip yesterday was a good 3hr run up the motorways and A roads all with me conciously driving above 2000 rpm at different loads where traffic allowed.

I was expecting to notice the "regeneration" phase and the light to go out but still a couple of short trips out and a tank of fuel I still have the light on...

We are heading home today so that will be another 100 plus miles under its wheels but what should be the next step if the light is still on?

I was planning to see an Audi Vdub indie and ask his opinion and try to avoid the stealership, anyone else have experience of light on and clearing after time or am I in line for a hefty bill??

Cheers,J

[Tame Technician]

You have to do the regen drive, if the DPF light comes on.

If you get the DPF light and the engine warning light (or the engine warning light on its own) it means somthing is wrong, and you need the fault memory read, all teh regen driving in the world wont make any difference.

I'd bet good money its the Exhaust Gas Differenctial Pressure Sensor (for the DPF) gone faulty.

[Lanky76]

Cheers tame will a good indie with vagcom spot this and what would one of them cost roughly?

[Spoons]

Tame Technician said:

You have to do the regen drive, if the DPF light comes on.

If you get the DPF light and the engine warning light (or the engine warning light on its own) it means somthing is wrong, and you need the fault memory read, all teh regen driving in the world wont make any difference.

I'd bet good money its the Exhaust Gas Differenctial Pressure Sensor (for the DPF) gone faulty.

That's what happened to mine, DPF light, did regen drive, 2 days later DPF & 2 warning lights and no perfomance whilst drinking 15 ltr of fuel in 30 miles. Thankfully sensor replaced just inside warranty.

[Lanky76]

Thanks for the responses.

Having looked into it further its not actually the DPF warning light its the orange engine symbol and its the Emission Control System warning light and its on constantly. The car is a 2007 A3 170 TDI with 75000 on the clock.

Off to see a guy with diagnostic kit at lunch time and will feedback.

[Lanky76]

Update: Just returned from having faults read and light turned off.

It came up with two. First one as TT commented was the Exhaust Gas Differential Pressure Sensor (for the DPF) and the second was the DPF itself.

He asked how I drove the car to which I answered conservatively.... he recommended giving it a good blast every once in a while to stop clogging of the DPF with grandad driving.

So fingers crossed it was just a warning to tell me to get my lead boots out again and wind the revs up a few thousand

[JeffC]

must be in the air, Ive just collected a A3 170 tdi with 90k slow as a slug in limp home mode, both glow and engine managment lights flashing and big picture of a exhaust and particulate filter see owners manual in the obc.

In this instance will this be the particulate filter ? or could it be a sensor? and is the sensor an easy swap as I have another 170 A3 that is perfect so would help diagnose .

Ps priced up the Pdf fron audi and was pleased I was sitting down!! £1200 plus vat !

Edited by JeffC on Monday 19th July 17:02

[Tame Technician]

Lanky76 said:

Update: Just returned from having faults read and light turned off.

It came up with two. First one as TT commented was the Exhaust Gas Differential Pressure Sensor (for the DPF) and the second was the DPF itself.

He asked how I drove the car to which I answered conservatively.... he recommended giving it a good blast every once in a while to stop clogging of the DPF with grandad driving.

So fingers crossed it was just a warning to tell me to get my lead boots out again and wind the revs up a few thousand

When the pressure sensor isnt working the car cant tell how clogged the filter is, so it always also loggs teh code to say the filter is clogged, but its a spirious reading the filter is fine just teh sensor playing up.

I fit maybe 4 or 5 a week.

[Tame Technician]

JeffC said:

must be in the air, Ive just collected a A3 170 tdi with 90k slow as a slug in limp home mode, both glow and engine managment lights flashing and big picture of a exhaust and particulate filter see owners manual in the obc.

In this instance will this be the particulate filter ? or could it be a sensor? and is the sensor an easy swap as I have another 170 A3 that is perfect so would help diagnose .

Ps priced up the Pdf fron audi and was pleased I was sitting down!! £1200 plus vat !

Edited by JeffC on Monday 19th July 17:02

IF the filter just needs regenerating you only get the DPF light, Glow plug and or engine light and there is a fault, can be any number of things, code read first.

If you get the glow plug and DPF light it is a fault relaited to the DPF, usually the pressure sensor, but can be one of the exhaust gas temp sensors or the filter it self.

[Lanky76]

Thanks Tame, I think you must be right the Engine Mangement Light came on again this morning.

I will head back to the guy at lunch and see what he says.

Tame if you do these so often can you let me know a price for the part (part number if possible) and let me know how long the job takes?

Many thanks

[DPX]

Tame Technician said:

Lanky76 said:

Update: Just returned from having faults read and light turned off.

It came up with two. First one as TT commented was the Exhaust Gas Differential Pressure Sensor (for the DPF) and the second was the DPF itself.

He asked how I drove the car to which I answered conservatively.... he recommended giving it a good blast every once in a while to stop clogging of the DPF with grandad driving.

So fingers crossed it was just a warning to tell me to get my lead boots out again and wind the revs up a few thousand

When the pressure sensor isnt working the car cant tell how clogged the filter is, so it always also loggs teh code to say the filter is clogged, but its a spirious reading the filter is fine just teh sensor playing up.

I fit maybe 4 or 5 a week.

4 or 5 a week , this is silly . I have also had DPF problems and it has spoilt the car and the reason why it was purchased . Mine is not driven conservatively it spends at least 12 hours a week on the Autobahn at 180+kph and it still clogs up.
I can now feel when its doing a regen and its down to 3rd and the car gets thrashed under load up some of the windy hills in Germany . It takes about 15 minues to clear , oil temp drops and all is normal .

The handbook should say "Drive it hard for at least 15 minutes" above 3,000 and with all the load you can on the engine . Keep on driving until you see the oil temp return to normal.

I will not go near another car with a DPF when its time to change.

[JeffC]

had mine in today 1st time ive driven the car, had to drive 5 miles each way, wouldnt rev over 3,000 rpm just cuts out, just limped up a slight hill in 2nd gear which is normally a 60mph 6th gear hill!when got there sensor checked out ok vacum pies that go to it were not blocked so for me its looking the like the dpf is donald ducked .

[Tame Technician]

Lanky76 said:

Thanks Tame, I think you must be right the Engine Mangement Light came on again this morning.

I will head back to the guy at lunch and see what he says.

Tame if you do these so often can you let me know a price for the part (part number if possible) and let me know how long the job takes?

Many thanks

No idea what the price is, all the ones I've done were under the 3 year waranty so we dont price them up. Part number depends on your vehicle, so ring your local audi centre or TPS and give them your chassis number for a price.

Takes under an hour to fit.

[Lanky76]

Update: well a for Tame Tech, I had the Exhaust Gas Differential Pressure Sensor replaced and this has extinguished the Engine Management light. Been out for a few days now.

Cost of part £41 and half hour labour to fit.

Fingers crossed it stays out and the DPF doesnt play up now.

Thanks to all who commented