B6 1.9TDI 130 EGR valve clean/Mod?

[BIG_BOZ]

I have done some reading about possible reasons for my 52 plate 130 with 129k miles on it being a bit Smokey of late and i think my EGR might need cleaning, I have never done it and have no idea if it has ever been done before.

What i don’t know is how i can tell if it needs doing, and also numerous forum threads (not on here) suggest a bypass mod for the EGR where (i think) the EGR outlet to turbo pipe is disconnected from the EGR and fed from the ambient air (i assume with a little filter on the end of the pipe) and then the outlet from the EGR is banked off. I understand the theoretical benefits of this given that this is effectively like having a Cold air feed to the turbo so it is ramming cold air into the engine and not warm air, but I don’t know if there are any related issues with doing this.

What i can’t find is definite confirmation of how to do this and diagrams to show which pipes to disconnect/blank off.

Anyone done this or have any EGR based advice?

Cheers

[cruiser647]

You've sourced a replacement for your old PD already? After the write-off?

On my old Bora PD, I just removed the air tube and then sprayed plenty of Carb Cleaner into it, fiddling about with the mechanism to open the flap. Wait awhile and then started the car - watch for the smoke!!! But that should help a bit. You can also clean it with rags and stuff after you've sprayed the stuff in.

Whilst there, clean the MAF but do it GENTLY!!!!

[BIG_BOZ]

You've sourced a replacement for your old PD already? After the write-off?QUOTE]

No, it got repaired, I was very surprised by this but gave the car a very thorough once over on a ramp and it all looks hunk-dory and the repair was done to a very high standard. Had a fun afternoon fitting all the stuff back on that I took off! They even repainted the Towing Eye which had been scratched, and put a new Radio Ariel in (not the window, the box at the top of the rear window under the panel on the roof) so a very well done repair.

Regards the EGR, This is my understanding of what it is doing and why cleaning it is required.

So.......the EGR is sending some of the waste exhaust gas back into the engine via the turbo, I assume to reduce emissions, thus the valve and pipe work gets "gunked" up by the crud in this re-cycled gas, unburned fuel and carbon?. Spraying a load of carb cleaner in I assume just dissolves the crud which is then sucked into the engine and is burned off resulting in a cloud of black smoke as it all gets combusted……is that right?

So cleaning the valve and pipe work out gives a benefit to the quality of the air going back into the engine, and also improves the general breathing. In the same vane therefore, I assume it is worth doing the EGR Bypass to stop this re-cycling process and direct cold air into the turbo instead of this warm re-used gas, thus increasing combustion efficiency and in theory power and torque and fuel economy……….to the detriment of the environment obviously in that the dirty gas is no-longer being re-cycled and is just going out the exhaust pipe?

The MAF got replaced just before I bought the car on 88K, and the 50k miles since then has been mostly on Bio Diesel which is cleaner than DINO so im fairly confident that the MAF is OK but I will have a look at it while im there.

I don’t get any warning lights, its just a bit Smokey in the mornings and if I boot it on the M-Way at night i can see smoke in the headlights of the car behind me (albeit white smoke that smells of chip fat as its Bio), also economy is still as expected just want to do some preventative jobs before the weather closes in.

[Mook]

The EGR is exactly that - and Exhaust Gas Recirculating valve, and yes, it's to reduce emissions.

Blocking it off means you're getting 100% clean air, rather than some recirc'd exhaust, but the temps will make sod all difference, as the charged air gets heated by the turbo (and then goes through the intercooler).

If you're blocking off the recirc valve, to do it properly you'll need to get the ECU map adjusted to take account of the difference in emissions.

[cruiser647]

Also, however clean your exhaust gases look in the daytime (you'd be hard pushed to see anything) at night in headlamps it looks awful - but in reality, it's nothing much.

[BIG_BOZ]

Cheers again, Think i will just clean it out and not bother with the bypass, its remapped to 163 with a Revo anyway so its quick enough.

However, someone on the Vegoildiesel forum has suggested that the EGR can be switched off via VAGCOM. Is this true? I have to plug the car in and Re-activate the Cruise, so could turn it off at the same time. I assume this would just prevent the valve from letting any re-cycled exhast back in?

If so anyone know how to do it?

[Mook]

If you want to switch it off, then just unplug it!

Regardless of how you do it, you'll be best advised to get your ECU map changed to take account of it. As for a Revo map giving 163PS? I wouldn't believe any figures you've been given by them. It's probably around 150bhp, but if it goes well enough for you, then that's all that counts.

[BIG_BOZ]

If you want to switch it off, then just unplug it!

Regardless of how you do it, you'll be best advised to get your ECU map changed to take account of it. As for a Revo map giving 163PS? I wouldn't believe any figures you've been given by them. It's probably around 150bhp, but if it goes well enough for you, then that's all that counts.

Hadn't thought of just unplugging it!

Im sure the Revo gives 163BHP....on a 10k mile car not a 130k miler like mine!. I would think 150 is probably about right, Bio has less energy in it too so under no miss conceptions that its over 160.

I can tell you for sure though that it pulls significantly better than a standard 130 TDI Passat of the same vintage, I drove the 2 cars back to back when i bought the Audi. Massively quicker through the mid-range, gives the Traction control a run for its money in the wet too.

Does for me just fine!

[Mook]

Revo will quote that figure. Putting that figure out on a dyno is a wholedifferent thing

[BIG_BOZ]

Revo will quote that figure. Putting that figure out on a dyno is a wholedifferent thing

My Mum used to have a Leon R that was 225 as standard on the old 1.8T 5V VW engine. The Revo on that quoted 272, but it was Rolling Roaded at 281 with no other Mods, i think it had done about 20k miles when she had it done so was nicley run in. That thing was a beast!

[Tipex]

160 odd isn't a particularly unrealistic figure for the 130pd engine, it's a very tuneable lump, and a cracking diesel engine.

Mine had a Dragon Digital tuning box on it (shhh, don't tell Shark or he'll castrate me), and was rolling roaded twice, once when I first put it on, then again at 130k miles just because I was curious.

The first run, after tinkering with the boxes settings, resulted in 171bhp, and the second, at 130k miles threw up 175bhp.

Now I know how the figures can be over inflated etc etc, but the operator had no need to do so, as I wasn't spending anything other than the rolling road session with him, so although you can take the figured with a small pinch of salt, 160bhp should be perfectly achievable.