AWX or AVF in my 2000 B5 A4?

I'm about to get another engine for my B5 Audi A4, with an ATJ coolantoholic (for the third time) in it at the moment. I was wondering which engine code would be the better choice, with possibly some tuning in the future on mind.
I've been seraching for 1.9 8v PD-TDI, to retain compatibility with the wiring harness, and hopefully the imo.

Would AWX or AVF be good choices?

Thanks alot!

AWX 5spd, AVF is 6 spd with bigger clutch to handle more torque, and it also has more torque (310nm vs 285nm) so go for AVF

Another reason to go for the AVF is that the uprated 240mm clutch set ups are much better that the 228mm ones....

Note that some AVF and AWX engines have smaler nozzles than others. IIRC AWX and late model AVF have the smaler ones, the middle model (2003 or so ) have larger ones, and the first AVFs had the same nozzles as ARL engine.

Interesting.... My uprated 228mm SRE clutch is holding up nicely, but yes 240mm clutch would be preferable.

bhodgkiss said:

Interesting.... My uprated 228mm SRE clutch is holding up nicely, but yes 240mm clutch would be preferable.

Click to expand...

Does the SRE set up utilise a paddle clutch?

leon10tagg said:

Does the SRE set up utilise a paddle clutch?

Click to expand...

Nope, organic clutch but you can also have a paddle clutch which is not for a daily drive...

Well my current set up is a 5 puck paddle.....its horrible and its in my daily....regards the SRE how much torque will it hold and what sort of price is it?

The 240mm SRE takes 565nm from memory? It's on their website.
But talking to Sachs you can add 20% (so well over 650nm)
£500 ish for clutch plate and friction disc?

So I went for an AVF from a 2003 B6. Very pleased with it!!
The engine was bought with 200k km on it. I believed it to be stock, but when it was delivered I noticed an ABT sticker on the ECU. I've had no luck trying to find number figures, even though I believe it to be a generic remap. A readout of the ECU by a tuner estimated ~140hp. Feels very smooth. Might be a custom tweaking for all I know. Information on this is appreciated!

Eventhough both the AVF and the old ATJ has 240mm clutches, I noticed a difference in design on both flywheel and pressure plate, so I swapped it over. Looking at sachsperfomance.com, the SRE package for ATJ holds 565nm, while slightly less for the AVF at 550nm.
As I did not want to take the plunge for the SRE, I put a new OE Sachcs in for now.
I also had to have the immo disabled, and fitting a B6 air cleaner with the larger diameter LMM.

I will check ETKA to see which nozzles it's got. How does the middle model's compare to the ARL's?

With regards to the nozzles, there's not much in it. 520cc vs 550cc. If you do have smaller nozzles, it's not really worth swapping to 550cc IMO. 5% fueling difference which can be made up by advancing SOI ever so slightly without affecting PCP.

What was wrong with the ATJ engine? Head gasket by any chance (Presuming similar to the PD115 AJM)?

Ash

Correct! Headgasket blew second time for me. I believe the head was face milled when it was changed the first time (third in sum), before I bought the car.
What's up with those engines blowing head gaskets? Do the heads warp? I could not find any cracks.

Thank you very much for information on the nozzles!

I'm not entirely sure tbh, but I've seen quite a few posts stating head gasket issues on the AJM, which I'm presuming is very similar to the ATJ. I'm not sure why though. It's said that PD115 (at least some of them anyway) engines had a higher 19.5 CR compared to 19.0 on the other PD engines (bar 18.5 on the PD150/160) and this had something to do with it. Maybe that plus weaker head bolts? Not come across a single report of a AMF PD75 1.4 TDI blowing a head gasket, and they're 19.5 CR too. There's a Polish one on youtube with over 750k km with only consumables being replaced.

Ash

I like the 1.4TDI Polo's, think they drive better than the new 1.2 CR.
In my engine's case, I guess the slight shaving of the head and 150hp/380nm generic mapping installed by the previous owner didn't help either.

Eivind

Hi f4ri4,

There are some differences between these two generations, at least for the Audis, where most of my experience lies. I am guessing it translates more or less to the Passat, but I'm not sure. You have a 3B Passat, and are dealing with a 3BG donor?

There's the type of fuel cooling: My car has an active setup, with a fuel-to-coolant heat exchanger on top of the fuel filter, an electric pump and a separate radiator with the same placement, but on the opposite side from the intercooler. The B6 has a passive setup, with a radiator that the return fuel passes through, under the car.
Then there's the additional heating scheme: The B5 use heating plugs in the coolant (in a small housing beside the tandem pump), where the B6 use a PTC element for heating HVAC air directly.

These differences (and maybe more that I don't remember) means you will have to swap the wiring harness over from the ATJ to the AVF.

There may also be differences in the immo versions between the generations. If that's the case, the "new" ECU won't program to your instrument cluster.
You can get immo removed from the ECU (like I did), or you can get the AVF files put on your existing ECU.
I am currently trying to do the latter, to get rid of the flashing immo light and to put a new tune on it.

One more thing: I had to pull a relay from under the dash on the drivers side. This was constantly clicking, as the "new" ECU was trying to PWM control the electric cooling fan. Without the relay, it seems to operate like normal for the B5.


Eivind

Hi Elvind

You're right

I have this problem from the relay under the dash, but i cant figure it out wich on it is.

Can you tell me, what relay did you mention? Its only take it out and problem solved?

For me that was the case yes. I took the relay out, and things seem to work normaly.
I think on my car it was the leftmost relay on the upper row, kind of hard to get to. But just feel the relays – I think you should be able to feel vibration from the one buzzing.

Hope this helps you.

You may want to look into a Passat 3BG ECU file as a basis to resolve the cooling fan relay issue (or just leave the relay out for good). They are sort of a hybrid between A4 B5 and B6. The 3BG runs the AVF engine but still has the main cooling fan running mechanically driven by the v-belt like the B5 (A4 B6 has an electric main cooling fan). Other than that, same setup as in the A4 B6 with updated (simplified) fuel cooling and such.

With the new engine coming from a Passat in f4ri4's case maybe the relay has actually to do with the fuel cooling? I'd personally prefer the passive cooling as found on the AVF. Less stuff that can fail. But no idea if its easy and inexpensive to install. Good luck with your swap.

Rewease: I believe the B6 still has the mechanically driven fan. Atleast my brother's '03 with the AVF engine. Maybe this was a change incorporated on the B7?
I worked on a B7 PD140 2.0 8v the other day, but can't remember the fan setup.

I agree with you the updated fuel cooling is a smoother setup, that I considered. Unfortunately I had a hard time finding a good spot for the radiator underneath the B5.
Getting rid of the fuel cooling radiator in the bumper area would free up space for an RS4 style twin intercooler setup aswell.

My brother's AVF has the smoothest tune BTW – from a Norwegian company called TS Racing. It is supposed to be a 160hp 380Nm tune I think (not a hundred percent sure about the torque). EV-like linear acceleration only WITH engine sound. It doesn't hurt the performance or consumption it's not a quattro either. I couldn't live without quattro in the winter though

How did your swap turn out f4ri4?

You are right, they changed the fan to electric later in the B7. My bad.

The AVF stock setup really makes you wonder. Tuned mine a little myself and from stock it has all its torque between 1900 and 2200 rpm. With higher rpm the injction quantity limit only goes down. Typical early PD feeling: First you get a punch, then suddenly nothing as it revs up.
I tuned it without even increasing max torque (for now) but making it last beyond 3500 rpm. Drives a lot smoother and also did not increase consumption.

f4ri4: Heres a swap from the 115HP AJM to AVF.
http://www.passatplus.de/umbauten/motor2/