2014 Audi A8 TDI, post emission fix

Car is noticeably slower, and lacks the same low end torque.

Previously, if you floored it, the car would stay in a tall gear and use the low end torque of the engine. Now? Now the torque is far more subdued, and the car will instead downshift use the hp instead. It's definitely less satisfying.

Dealer also said DEF fluid usage would double.

I'm also dissatisfied with the fix. My engine coolant is always over 200F. It does hold gear for longer, not sure if it makes it faster though. Got my second 5k back, will be using on a Malone tune and down pipes if I don't end up selling it.

Zawurah said:

Car is noticeably slower, and lacks the same low end torque.
Previously, if you floored it, the car would stay in a tall gear and use the low end torque of the engine. Now? Now the torque is far more subdued, and the car will instead downshift use the hp instead. It's definitely less satisfying.
Dealer also said DEF fluid usage would double.

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Was there anything wrong with the existing threads where gen 2 3.0 owners reported? I know the A8 is top of the line, and all, but come sit in coach with the rest of us.

mythdoc said:

was there anything wrong with the existing threads where gen 2 3.0 owners reported? I know the a8 is top of the line, and all, but come sit in coach with the rest of us.

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lol ?!

Noticed today that during engine startup, engine is not nearly as smooth and there's some mechanical pinging sounds coming from the engine. After warmup engine was smooth and no more pinging noise.

Not so happy.

I also own an A3 TDI, A6 TDI. Not that high and mighty, I just like a comfortable car.

Looks like getting ECU tuned will not revert the update?

Maybe a bench flash would fix it? Lost as to what to do. Would it be unethical to revert to old ECU firmware? EPA is giving temporary green light to keep driving on old pre-fix ECU. Could do that until they revoke the temporary pass on people holding out on getting the fix.

Could one theoretically buy a nonflashed/prefix ecu and put that in the car, have the dealer do the fix, then put old ecu back in.....is it only an ecu tune?

osu s2k said:

Could one theoretically buy a nonflashed/prefix ecu and put that in the car, have the dealer do the fix, then put old ecu back in.....is it only an ecu tune?

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^This is exactly what I had a friend do. I had him buy an ECU out of a salvage yard before the fix started. Then he installed that one, got it "fixed", then replaced his again.

ToxicDoc said:

^This is exactly what I had a friend do. I had him buy an ECU out of a salvage yard before the fix started. Then he installed that one, got it "fixed", then replaced his again.

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No problem with the car recognizing the VIN on the salvage ECU? Would be weird for the ECU recognizing all the parts

You’d have to change out and replace both the ECU and the TCU modules. Of these, the TCU is more important, b cause there are not tunes readily available for them.

Don't recall the details sorry. He ended up selling the car though. Might be worth looking into. How does someone replace a bad ECU?

Zawurah said:

Dealer also said DEF fluid usage would double.

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Even though its not the same car/engine, we just got the warning light for low DEF on our new 2015 Passat, light came on just shy of 15K. we bought it last April with 35 miles on it, usage prob went up but 5 galls for 15K miles isn't bad.

Take the pile of cash VW/Audi gave you and you can make the A8 a rocketship better than before, pretty easy.

Not sure how the 3.0 will fair.

Does anyone have part numbers for tcu and ecu.

Zawurah said:

Car is noticeably slower, and lacks the same low end torque.
Previously, if you floored it, the car would stay in a tall gear and use the low end torque of the engine. Now? Now the torque is far more subdued, and the car will instead downshift use the hp instead. It's definitely less satisfying.
Dealer also said DEF fluid usage would double.

Click to expand...

Get the Malone Stage 2 tune and you will fall in love with your car again. I got it for my A6 TDI and absolutely love it.
Yeah there are possible warranty implications, but that is the risk with every ECU tune.

Darkone said:

Get the Malone Stage 2 tune and you will fall in love with your car again. I got it for my A6 TDI and absolutely love it.
Yeah there are possible warranty implications, but that is the risk with every ECU tune.

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Is Malone doing stage II tunes for the fixed 3.0L PC2 cars already?

Had the update down 1,500 miles ago at 42,800 at 44,200 the Adblue countdown came on. So it's looking like 2,500 till empty on the Adblue. Good thing the Audi dealership is 3 blocks away!

tdiesling said:

Had the update down 1,500 miles ago at 42,800 at 44,200 the Adblue countdown came on. So it's looking like 2,500 till empty on the Adblue. Good thing the Audi dealership is 3 blocks away!

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Highly likely they didn't fill it up at time of emissions repair. I'm at 3500 miles on my 2016 A8L and no warning yet.

Doing an ECU tune will not completely change the car behavior, and will only give more power. So unless you downgrade, the new behavior such as cold start loud and rough idle will still be present. Downgrading to pre-fix ECU is the only way to revert the undesirable behavior.

It appears you can downgrade the ECU firmware using either engineering mode VW hardware/software (ODIS-E), or using VagCan cable. I will give VagCan cable a shot.

This ECU firmware downgrade you speak of, is there any information online that discusses it more? Thanks for your help.

MBQ said:

Is Malone doing stage II tunes for the fixed 3.0L PC2 cars already?

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Yes, we had 20+ ECUs bench flashed and databases built within 2-3 weeks of the emissions update being released, thank you to everyone who helped out there. Bit of delay on some oddball ECUs, couple particular Q5s and A6s that're less common but it's all well covered by now. Also put ~2K on a 14 R line before/after the emissions update to directly test what VW did there, quite a lot of small changes, haven't had the time to publish anything. Pretty swamped to be honest and Mark can only do so much, if we ever find the time we'll do some marketing. Working on Transmission tuning and more custom adjustments for hybrids as well.

An ECU tune does more than just add power, it does affect injection timing which changes noise and power delivery. TCM tuning is needed for transmission mapping though unless you can make code adjustments in VCDS.

Downgrade successful!

I installed a junkyard ECU, and it had the original 004 firmware from the car's original release.

My car is now driving like it use to!! I can't get over how much better the engine behaves. Cold startup is smooth, once again it makes tons of torque, and even the shifting feels smoother.

I didn't notice any major changes when my little A3 2.0 TDI got it's fix, but the A8 fix is a mess and drives badly.


I reinstalled the 'fixed' ECU again, and now it's driving terrible again.

The EPA has a temporary pass for those that have not taken the fix. Would it be unethical to use the older firmware until the EPA revokes the temporary pass?

No, there’s plenty of vehicles out there worse for the environment ... drive away to your hearts desire....

Zawurah said:

Downgrade successful!

I installed a junkyard ECU, and it had the original 004 firmware from the car's original release.

My car is now driving like it use to!! I can't get over how much better the engine behaves. Cold startup is smooth, once again it makes tons of torque, and even the shifting feels smoother.

I didn't notice any major changes when my little A3 2.0 TDI got it's fix, but the A8 fix is a mess and drives badly.


I reinstalled the 'fixed' ECU again, and now it's driving terrible again.

The EPA has a temporary pass for those that have not taken the fix. Would it be unethical to use the older firmware until the EPA revokes the temporary pass?

Click to expand...

That's an individual question; it would certainly be illegal but not necessarily criminal. Personally I would drive it with the old ECU until I had no choice on doing the stage II fix. Then I'd reinstall the original ECU for it. Then I would see how it drove.

Zawurah said:

Downgrade successful!
I installed a junkyard ECU, and it had the original 004 firmware from the car's original release.
My car is now driving like it use to!! I can't get over how much better the engine behaves. Cold startup is smooth, once again it makes tons of torque, and even the shifting feels smoother.
I didn't notice any major changes when my little A3 2.0 TDI got it's fix, but the A8 fix is a mess and drives badly.
I reinstalled the 'fixed' ECU again, and now it's driving terrible again.
The EPA has a temporary pass for those that have not taken the fix. Would it be unethical to use the older firmware until the EPA revokes the temporary pass?

Click to expand...

Was the ECU just plug and play or did you have to do anything with VAGCOM to make the car work? What does a junkyard ECU cost?

OP: you found an interesting way to solve your problem, but I think the better option for others in your position would be to insist on being taken seriously and properly helped by Audi.

I'm assuming you had to reprogram the ECU to work with the immobilizer system? Doesn't swapping out the ECU put your extended warranty at risk? Possible ECU/TCM mileage log mismatch?

Odometer mileage is stored in the dashboard. Ecu's fail, and do need to be replaced.


I've grown use to the fixed ecu, and I don't care anymore.

Zawurah said:

Odometer mileage is stored in the dashboard. Ecu's fail, and do need to be replaced.
I've grown use to the fixed ecu, and I don't care anymore.

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Sounds like the fix has beaten you into submission