Alfa 156 selespeed delayed shift

[Dr_Doom]

Hi, after a while I am now starting to run into a few problems.
This is an intermittent issue where the gears may shift crazy on their own or just slip into neutral.
A couple instances I could not get any gear engaged, somehow it works after I leave it for a while.
One thing that happened is that I could not engage 1st, only reverse. Then after shifting multiple times to hopefully get into 1st it works, sometimes going back to neutral or staying in gear. Then after taking off 2nd is not working correctly, sometimes skipping it or engaging 2nd, but then "engaging" 4th (it still feels like 2nd). From 4th I can shift down to 3rd and when I shift to 2nd, it changes to 4th almost immediately.
No error messages pop up on Multiecu and for some reason it only happens in the very early morning. Maybe temperature is a factor?
I am leaning towards the two selection and engagement sensors needing replacement, but I'm not sure if something else may be at play. I also want to figure out how to test the possible faulty parts so I can replace the correct part.

Think you may have any ideas?

[bazzbazz]

Your assumption about worn/faulty Selection/Engagement sensors is a good place to start. These can wear to the point of causing such issues but still not throw up an error and will also pass the EOL calibration as well.

Now, you may want to be sitting down when you get a price for them as the PF2C Sensors are getting harder to find and are therefor becoming stupidly expensive, as such the price on them has just gone up. Alfaworkshop in the UK are selling them for around AU$345.00 ea. There are some places here in Oz still selling at the older/cheaper price, try Italian Automotive Spares in Melb or Arese Spares in Sydney.

Just one little piece of advice, DO NOT try to attempt to substitute cheaper alternative sensors, they will only cause you trouble, you want Magneti Marelli PF2C, Alfa part #71716195. And don't bother with trying to use used items either, as they will have wear in them as well, so wasting your time. You have been warned . . . . 


However, before buying set may I suggest that you do two things if you haven't already done them first -

1/ Clean the large 20 pin Actuator connector that sits between the battery and the thermostat.
2/ And as I have mentioned before Re-Torque the "Pinch Bolt"

[Dr_Doom]

Is there a way to test the sensors to see if they are good? Maybe checking resistance is within a correct threshold or something?

[Tubbs]

I'm assuming this is the same senor at a better price.

https://spareto.com/products/magneti-marelli-sensor-throttle-position/219244240500

[bazzbazz]

As long as the one they supply is actually a Magneti Marelli item then it's an outstanding bargain. Well spotted.

[Tubbs]

Is access to the pinch bolt easy without removing the gearbox as Doom did?

I occasionally experience the same problem. Driving along an all of a sudden it drops to neutral, when shifting down. You can hear it click around trying to go into gear. It is resolved by taking the key out, unplugging to Selespeed loom, plugging back in and it is good to go. Not sure if this actually does anything or if it is just coincidence.

I have changed the sensors around but it happened again. That's how I found the spareto ones when looking at new ones.

[bazzbazz]

Access is through the LH front wheel well.

After removing the LH wheel you will need to lower the gearbox a little by supporting it with a jack and undoing the three bolts that attach the engine mount to the frame, then slowly lower it until you have access to the Pinch Bolt.

Remove the sealing plug and you will now have access to the pinch bolt hole. You will also have to remove the rear right Actuator mounting bolt as it partially blocks access to the pinch bolt.

Pinch Bolt Torque is between 27nm - 33nm.

[Tubbs]

Great guide, thank you.

Are the three mount bolts easily accessible with the wheel off?

[bazzbazz]

Yes

[Tubbs]

Thank you, it will be a job for the holidays.

Came across this video showing the pinch bolt locations.

https://www.youtube.com/watch?v=1Jx71nwbtdg

[Tubbs]

This may seem obvious but is this the mount that needs lowering?

[bazzbazz]

Yes

[Tubbs]

Cheers, thank you. I checked as you mentioned three bolts but there is only one at the bottom.

Need to get the undertray off now.