Why do you need to do that?

 

The car randomly goes into limp mode. I have DTCs for the steering wheel torque sensor and the sensor gives nonsense readings intermittently. I suspect the sensor could be the root cause and apparently one has to replace the whole rack.

 

I have had the subframe out of my car in the past, and I am pretty sure you will at least need to lower the rear of the frame to get the rack out.


You will need to unbolt the rack from the frame before you drop it, and that should just about give you enough room to get the rack out to the side.

If not you will have to remove the whole subframe, which is a right ball ache of a job.

 

Could also be worth checking the battery voltage. Odd things happen when they fail.

 

You can't measure resistance in a circuit with the power on.
A fuse has a small resistance but not what you could measure with a nomal meter.
A bad connection may appear to have little or no resistance when measured as the meter passes such a tiny current through it.
What are you measuring 5-8mv across? A fuse or connector will have a slight voltage drop across it which will increase as you draw more current (Ohm's law). 5-8mv is next to nothing (and probably at the limits of what your meter can accurately measure).
You maybe need a better understanding of electronics before coming to the wrong conclusions.
I'd check what people have already said: bad connections and battery (even if the battery seems okay).

 

What are you measuring 5-8mv across?

It was from negative battery terminal to ground connections. This was going up as I was putting more load on the battery.

 

I had the steering rack replaced with a used unit and the steering wheel torque still spikes to 900Nm. This is the same thing as before. Can someone with a Giulietta MA 1.4 pre-lift check that parameter in MES or AlphaOBD is not spiking to over 900Nm when slightly touching the steering wheel? This is in case spiking to over 900Nm happens on every G and I was looking on a wrong thing.

 

I pulled the plugs from the steering rack and probed them with a multimeter. There are two thick power wires, which seem ok. There are also three thin wires, marked 1 2 3 on the socket. 1 and 2 must be CANBUS hi and lo because there is 60ohms resistance between them and about 2.5V across to battery ground when key is in mar. I don't know what nr 3 is. I was expecting ground, but:

a) when the key is off, there is only 170ohms resistance from the battery ground, and a couple of mV voltage across to the battery ground
b) when the key is in mar, there are about 12V across to the battery ground

Does it make sense to anybody? Is that how "weak ground" manifest?

 

I don't know what nr 3 is. I was expecting ground, but:

a) when the key is off, there is only 170ohms resistance from the battery ground, and a couple of mV voltage across to the battery ground
b) when the key is in mar, there are about 12V across to the battery ground

I found that nr 3 is "The ignition-operated supply". So I guess this is normal.

 

Is this the same thing that sometimes happens on MiTos?

 

There are differences. Mitos lose power steering and don't enter limp mode when they have problems with the steering sensors. My G doesn't lose power steering and enters into limp mode. No codes in the engine module. I described it in another thread: https://www.alfaowner.com/Forum/alfa-giulietta/1169949-limp-mode-c1221-c0074-c100a.html

PS Mitos have different power steering solution (engine and sensor placement) and from a different manufacturer.