D3 4.2TDI DPF issues

[ainarssems]

Originally Posted by paulrstaylor

On the 3.0 the DPF sensor is easily accessible on the firewall at the rear of the engine.

On the 4.2 they were clearly struggling with packaging, so they fitted them on top of the transmission.

30 mins to replace on the 3.0, oficcially gearbox out and ~8 hours on the 4.2

I know, right? Could not they find a better place?

According to Elsa it's 0.4 hours for 3.0 TDI, and 1.3 hours for one sensor on 4.2 or 1.6h for both sensors not including adaptation. Gearbox does not have to come out, you just unbolt subframe and lover gearbox a bit to reach to the sensors, still not something I am looking forward to do on drive.

On smaller cars with 2.0TDI it's easily accessible under bonnet, can be done in 5 min.

[paulrstaylor]

It reaistically can be done in much less time, by only lowering the gearbox and having thin arms, but in any case the parts were relatively cheap hence I did both at once.

Sadly for Ainars the previous owner of his decided to save a few quid

[paulrstaylor]

Originally Posted by ainarssems

I know, right? Could not they find a better place?

According to Elsa it's 0.4 hours for 3.0 TDI, and 1.3 hours for one sensor on 4.2 or 1.6h for both sensors not including adaptation. Gearbox does not have to come out, you just unbolt subframe and lover gearbox a bit to reach to the sensors, still not something I am looking forward to do on drive.

On smaller cars with 2.0TDI it's easily accessible under bonnet, can be done in 5 min.

SOunds like they have changed the procedure in Elsa, but it is absoluetly possible to do it as you say - much easier on a ramp, can see it being a pain on the drive - good luck.

BTW, the 3.0 is the same as the 2.0 - 0.4 hours in Elsa is ~ 5 mins it seems

[ainarssems]

Got the sensors today but the wrong ones. at first I thought I have been sent wrong ones but when I checked ebay order they are what I ordered.

I just put in part number 07Z906051A when searching for them and ordered the genuine Audi ones that came up for a good price without double checking the number so have bought 079906051A. I can replicate the results on ebay, searching for 07Z bring up both 07Z and 079. Looking at some aftermarket sensors they are listed as compatible with both 079 and 07Z and also 03G. The difference is 1 mounting hole on 079 and 2 holes on 07Z but since aftermarket parts are listed as compatible with both so electrically they should be the same. I am also not sure they are original Audi, they do have part number on but came without any packaging and were a bit cheap for OEM.

Not sure what to do now, if they were easily accessible under bonnet I would give them a try but considering the work involved I don't really want to mess around. But not doing them tomorrow would mean to wait till next weekend

[homer simpson]

Originally Posted by ainarssems

Got the sensors today but the wrong ones. at first I thought I have been sent wrong ones but when I checked ebay order they are what I ordered.

I just put in part number 07Z906051A when searching for them and ordered the genuine Audi ones that came up for a good price without double checking the number so have bought 079906051A. I can replicate the results on ebay, searching for 07Z bring up both 07Z and 079. Looking at some aftermarket sensors they are listed as compatible with both 079 and 07Z and also 03G. The difference is 1 mounting hole on 079 and 2 holes on 07Z but since aftermarket parts are listed as compatible with both so electrically they should be the same. I am also not sure they are original Audi, they do have part number on but came without any packaging and were a bit cheap for OEM.

Not sure what to do now, if they were easily accessible under bonnet I would give them a try but considering the work involved I don't really want to mess around. But not doing them tomorrow would mean to wait till next weekend

This is the problem with ebay listings, a lot of sellers put in 'compatible' or similar numbers in their listing specifics to help them gain more exposure. If you are unsure, return them as you don't want to spend all that time and labour for them to be incorrect.

[ainarssems]

I think I will give it a try.

3.0 A6 used 076, 07z and 059 part numbers
3.0 Q7 used 07z and 059, 4.2 Q7 059
A8 3.0 and 4.2 both used 07z

I do not need to fully assemble it to test, I can test and see if it brings up fault code and compare readings to the other bank.

[ainarssems]

The sensor has dies completely now, no readings at all , stays at 0 mBar. No more DPF error P2002, just P2453 for the sensor. This does not throw up error light and no limp mode / reduction in power. So in a way it's good news, I do not need to rush into changing sensor and could send the wrong ones back and get correct.

I understand if the sensor is not working ECU will start regeneration based on the mileage since last regen instead of readings from the sensor. It's not ideal long term but does not stop using car to full potential in the meantime. The problem is sensor could start partially working again and give the wrong readings causing limp mode. I will have a look under car today anyway and see if I still want to try to change it today or maybe unplug it for now if it's possible with less dismantling and wait with change until I get the right ones.

[paulrstaylor]

100% your call, but I ran mine for a couple of weeks, while various dealers tried to work out how to do it, and the symtoms got gradually worse until the "limp mode" was barely able to move the car.

If it does kick in and get to that state, factor in a tow truck! i.e. get breakdown cover if you haven't already

Or just use the S4!

[ainarssems]

I had a look last Saturday but opted out of doing it myself and sent the wrong sensors back for refund. Car has been working without faults most of the week then started getting fault codes again on Friday. As I was not going to change it I was considering remap and DPF removal again, most remap places would not do it. One place that was happy to do it wanted £750, apparently they need to unplug DPF sensors when switching off DPF so it's the same job as changing sensors, dropping subframe with gearbox to get to them.


So I was back looking for a garage to change sensor but most are not interested, must be too busy. It's booked in for Monday now but they refused just to change the sensor and could not give price, said they need to put it on diagnostics and check themselves first for a fixed cost of 0.5 hours labour and then when they have diagnosed it then they can give price for the fix.

[paulrstaylor]

That doesn't sound great, I can understand them wanting to take a look to see what they are getting into, but wanting to charge you to do so isn't great!?