Steering rack upgrade from PR-1N2 to PR-1N4

[Jay-Jay]

Hi to everybody,

my steering rack has gained a considerable play and I want to take advantage of the situation to make another upgrade by replacing it with the sportier steering rack version (PR-1N4) which is factory installed on 6R GTI and R WRC models and also on every engine of Audi A1 8X pre-facelift (part. Numbers are 6R1 423 055 F -> 6R1 423 055 M -> 6R1 423 055 P).

I had the chance to test drive cars with those steering racks and I can confirm that (apart from the steering assist coding) they have a much sportier steering ratio, which I really loved.

Luckily I found a used rack from a MY2013 6R GTI (6R1 423 055 M) in very good condition and at a very good price.

Now, before proceeding with the replacement, I am facing a doubt and I wonder if someone on here could help me figure it out.

PR-1N2 steering rack has the G250 sensor installed on the top of rack.
Instead it looks like PR-1N4 steering rack doesn’t have any G250 sensor.

How can I manage this?

Will I just need to modify the last digit of the Steering Assist coding from “0” to “1” and just leave the G250 wiring simply disconnected? Or will I need to do something else?


Thank you in advance for your help.

Jay-Jay

[iichel]

Hi Jay Jay, IIRC your car has ESP, right? In that case the G250 sensor is nothing to worry about. Your ESP module will provide the steering angle and rotational speed to the power steering module.

[Jay-Jay]

Yes, my car has the ESP (ABS Bosch 8.2i unit).
So, do you think I could just leave the G250 sensor's wiring disconnected?
Maybe I can do a try and disconnect the plug now and see if any error shows up.

[iichel]

I'm very confident you don't need any of the electric parts on the new rack.

[Jay-Jay]

That would be amazing!
Before starting the replacement, I will try just unplugging the G250 sensor's wiring and see what happens.
I will let you know
Thank you so much for now!

[iichel]

just to be sure, i don't think your car has the G250 sensor since you have ESP from factory.

[Jay-Jay]

If I'm not wrong, my Polo has a steering rack with part number 6R1423055D.
I didn't check under my car, but searching for images on Google I see that this rack has a G250 sensor on its top.
*confused*
Tonight I will give a look under my car and report here.

[iichel]

Yes all Polo 6R cars will have the sensor on the rack from factory, but not all have them connected. Only if the car has no G85.

[Jay-Jay]

That would explain why Polo 6R's steering rack (only PR-1N2) is used as a replacement for Polo 9N3's steering rack. Not all Polo 9N3s have the ESP and consequentially they need a G250 sensor.
As soon as I check under my car, I'll report here.

[Danypolo5]

I would take advantage of the post to ask if it is possible to mount the same rack (6r1423055p) on a 9n3 polo without esp (1.4 tdi sportline so sport chassis)

[ciclo]

I would take advantage of the post to ask if it is possible to mount the same rack (6r1423055p) on a 9n3 polo without esp (1.4 tdi sportline so sport chassis)

Interesting question. According to the diagrams for POLO 9N3 it is the same as for 6R, that is, if it has the G250 sensor connected (for 9N3 with ABS without ESP) it does not have the G85 sensor installed (for 9N3 with ESP).

We installed a G85 sensor in a 6R with an ABS brake unit - without ESP - and at least it worked for the static cornering lights data.
viewtopic.php?p=520550#p520550

So you can investigate yourself by installing the G85 sensor in your 9N3 and disconnecting the G250 sensor to find out to what extent it is possible to do what you want to do.

--- More info ---

6R (diagram that I posted in a recent thread).


My J500, 1.2 TSI (ESP).

The connector behind the drain tube is a simple connector/plug without wires. It corresponds to the wires that would go to the G250, but my 6R is with ESP (G85) so there are no wires there and not in the steering rack either.

9N3


T41 (6R... 9N3*)

[Jay-Jay]

Sorry for the delay, but I've been pretty busy and I didn't have time to check till today.
Well, surprisingly, my car not only has the G250 sensor, but also it has the wiring that connects it tot the steering pump.

I had to remove the airbox to see the G250 sensor's connector (I alaso had to spray a bit of brake cleaner, since the plug was completely covered by dirt of 13 years):

Then I removed the front left wheel and the wheel's arch and as you can see the G250's wiring is connected to the steering pump.



In the end I unplugged the connector from the pump:



I started the engine and drive-tested the car: no problem so far.
So, I guess I can replace the steering rack without compatibility worries.

[iichel]

you can check the coding of the power steering pump to see if it uses G250. and also, cover the open connector. the real enemy of these pumps is water. they are fragile.

[Jay-Jay]

My steering coding is *12**, so it uses the signal from G85 sensor, but I still wanted to try unplugging G250 sensor's connector to be 100% sure it's not used by something else (or at least to find a reason why it's plugged in).
At this point, I really can't understand why VW didn't installed a 6R1 423 055 K steering rack, which still is PR-1N2 but it doesn't have the G250 sensor.

Anyway

[...] and also, cover the open connector. the real enemy of these pumps is water. they are fragile.

Absolutely!
Most probably I will cut my G250's wiring (since I don't need it), leaving the connector plugged on the steering pump.
Otherwise, if I'll casually find myself in front of a used steering pump from a Polo 6R with ESP, I would take the "blind" plug that's already used by factory to cover the G250 connection.

[RUM4MO]

Why not just leave all the wiring as it is and connect that lead into your next steering rack pump - doing that would avoid you needing to safely protect the wiring going to that connector?