TDI Torque: Performance and Benefits

Hi everyone,
I recently bought an AUDI 80 B4 TDI, manufactured in May 1993, and I've already had the engine mounts and the front left control arm bushings replaced, as well as the fuel filter. However, I'm currently not satisfied with the performance. It doesn't really produce power until around 2500-2700 RPM, and below that, it doesn't feel powerful enough. Also, it struggles on the fifth gear, even when going uphill slightly.
What could be the cause? Could it be the turbo? Besides a chip tuning, what else could I do to improve its acceleration, and it shouldn't be too expensive!

Here's what I plan to do in the coming weeks/months:
Put a UNI pot on top (hopefully it will sound like CLICK). Maybe also remove the intermediate pot or use a dummy, and put a chip inside!
What do you think about it? Or, what advice would you give me?

Best regards, Mike.

Try using the search function (e.g., for information on performance issues).

Please try using the search function (e.g., for performance issues, etc...)

I also couldn't find a real answer to my question using the search function.

Best regards, Mike.

Hello,

"Hey, after you register and log in, you're first presented with this page:"
/newuser.php

What did you do to isolate the error?

Best regards, Rainer.

Hello,

'Hey, after you register and log in, you initially see this page, right?'
/newuser.php

What did you do to isolate the error?

Greetings, Rainer

hello,

Okay, so I don't have a diagnostic tool, nor the ability to quickly read the error codes.
I just thought I would reach out to people who have more experience and know more than I do, but so far, I haven't really been helped beyond being directed to the search function or other resources, which I find disappointing!
Isn't it possibly also possible to say something like: 'Take a look at this, maybe it's the problem, it could also be this...' without reading the error codes?

and I mean that neither negatively nor in any way negatively...

What I did to narrow down the error:
Fuel filter replaced.
LMM changed.
Turbo looks pretty good, but it was a bit sluggish initially.
Otherwise, everything seems to be in order. It runs smoothly and doesn't make any suspicious noises. However, since I've only had the car for about a month and a half, I can't really assess its condition very well.

Best regards, Mike.

Hello Mike,

"The error description somehow reminds me of the following dialogue:"
"My TV isn't working anymore, what could it be?" - "Hm, what exactly is the problem?" - "It's not working." ... "...it's probably broken, why don't you leave it here for a while"

So, if the fuel filter were clogged, you would primarily experience a loss of power, especially when the fuel demand is high, meaning under heavy load at high RPMs.
Isses bei Dir nicht, also was der Tausch erstmal (auf Fehlersuche bezogen) für die Tonne. Makes sense, right?
Mass airflow sensors: based on experience, they tend to provide low readings when measuring high air mass (expert articles, search), so it's likely the same issue with the truck.
Turbo: Are you hearing any noises? Also, what's your oil consumption like?

Basically: what happens when you floor the accelerator in the RPM range where the engine lacks power?
Black smoke, no smoke, whistling/hissing sounds?

Best regards, Rainer.

Hello Rainer,

'Some of it was scrap, but I got the LMM sensor for free, and the fuel filter cost me less than 25 euros, so it's all good!'

I almost never use the turbo... and regarding oil consumption, I have no idea how much oil I need... I can't tell you right now.

'When I'm driving on the highway in 5th gear, with the accelerator fully pressed at around 3100 RPM, nothing happens; the acceleration is zero! It's only when I reach approximately 140 km/h that it starts to accelerate again.'
I have no smoke, neither black nor white.
'Whistling sounds and hissing, I can't say for sure yet, but I'll listen to it once.'

I don't think it's insignificant that the car was purchased privately and had been sitting in a garage for almost 3 months beforehand... and a minor service was performed just one month before it was deregistered!

And thank you in advance!

Best regards, Mike

The LMM (lambda measuring module) is very expensive at the Audi dealership. If you got it for free, it might not be in good condition.

Is the source reliable, and is it a new part?

Best regards,
Uwe

Hi Mike.

You have the same engine as me, a 1Z, manufactured in 1993. Unfortunately, we both have the extremely torque-weak version of the first TDIs in the B4. A measly 182 Nm at 2100 rpm is a lot less than the later 1Z engines with 202 Nm at 1900 rpm. I was also initially surprised by the weak performance compared to the 1Z engine in a Golf 3. After installing a chip, cleaning the intake manifold (which was almost completely blocked by the EGR valve!), and disabling the EGR valve, there is now plenty of power.
Cleaning the intake manifold might work wonders. A faulty chip and a 'defective' EGR valve will then do their part to contribute to the problem.

Regards,
Hermann.

The LMM (Mass Air Flow sensor) is very expensive at the Audi dealer. If you got it for free, it's possible that it's not in good condition.

Is the source reliable, and is it a new part?

Best regards, Uwe

The source is reliable...

Best regards, Mike.

Hi Mike.

You have the same engine as me, a 1Z, manufactured in 1993. Unfortunately, we both have the extremely low-torque version of the first TDIs in the B4. A measly 182 Nm at 2100 rpm is a lot less than the later 1Z engines with 202 Nm at 1900 rpm. I was also initially surprised by the weak performance compared to the 1Z engine in a Golf 3. After installing a chip, cleaning the intake manifold (which was almost completely blocked by the EGR valve!), and disabling the EGR valve, there is now plenty of power.
Cleaning the intake manifold could work wonders. A faulty chip and a 'defective' EGR valve would then add to the problem.

Regards,
Hermann

Sorry that I have to ask you this question now... but where is the intake manifold, or the plenum?!

Here's a picture:
http://mitglied.lycos.de/ferkelbabe/Audi_80/DSCF1866_1.jpg

Wow, the engine bay of this Audi 80 is a real mess (compared to the Golf and Passat). But, the intake manifold is located where that silver canister is.

Best regards, WarLord.

@Warlord
I think the engine bay is a thousand times better than on the 35i. Probably, you've never tried to access the turbocharger or the pressure sensor on our transversely mounted engines .

@Tribune
Regarding your question: The intake manifold is the silver cast part located to the left of the large plastic cover. (However, it's not clearly visible in the picture.)

But what I notice is that your EGR system is already out of operation: On the left, next to the plastic cover, is the pressure sensor for the EGR valve. There should normally be a hose connected to it. Have you already disabled it? If not, it was probably your predecessor. Hopefully, you've already solved your problem: The 'hose removal method' only disables the actuation of the EGR, but not the EGR valve itself. If you're unlucky, the valve might be stuck in the open position... Try using the search function, as there are more elegant solutions. Also, it's a good idea to remove the part, clean it thoroughly, and check its function (again, use the search function)!

Here's a quer_1Z.



The metal part where I marked the connection for the boost pressure measurement hose is the intake manifold.

m;

I believe the correct way to disable the EGR valve involves installing a metal plate on the connection to the intake manifold. However, the plate shouldn't be too thin. Please don't use something like a thin sheet of tin. It should be at least 1mm thick steel. That way, it doesn't matter whether the EGR valve itself seals properly or not.

Regards,
Hermann.

erstmlas thank you for your tips...I finally found it now....

and I was, believe it or not, having the car's error memory read today, and the result was: no errors found!

Best regards, Mike.