Changing the Crank Position Sensor

It’s been a bit since my last entry. The weather’s been pretty awful, and Gudrun’s been running pretty well so there honestly hasn’t been a lot of need to do work. There was still that set of codes indicating a malfunctioning crank position sensor, so my next bit of work would be replacing that.

The sensor itself sits on the top of the transmission bell housing where it meets the engine. It’s a Hall effect sensor that “reads” the position of the crank by detecting the variance in a magnetic field caused by divots along the edge of the flywheel. This lets the engine computer know when to mix the fuel and when to make spark. Obviously it’s a pretty important component.

Getting it out isn’t hard, but it’s not exactly easy either especially if, like me, you have big hands. The conventional method is to remove the rearmost spark plug wire and reach behind the engine block with a wrench to loosen the single bolt that keeps the sensor on. However with my large mitts and the fact that the bolt, like most of them on my car, was a little stuck this proved to be difficult. What I ended up doing was using a socket on a universal joint along with an extension that allowed me to approach from the top. This was tricky in its own way, but it was still easier for me. Your mileage may vary.

It goes back in just as easily. The end results seem positive thus far. No more occasional stalling or hesitation.

Future Project

My The cylinder switch for the central locking system on the driver’s door recently came apart on me, and rather than fix it I’ve decided to add the first non-factory bit to my car: a remote entry system.

Pictured here is a lock control along with an original Volvo 240 lock actuator that I got off eBay, so even though remote entry was not an original option on this car half the parts will be Volvo original. I consider myself a little bit of a purist when it comes to what goes into Gudrun, but I’m comfortable with this arrangement and look forward to being able to soon lock and unlock my car from a distance. That’ll have to wait until the weather improves because it’s been darn cold recently. Exhibit A:

That’s a solid layer of ice there, but I’m happy to report that she started up and drove without a problem. The cold air has also shown me that the clamp connecting my resonator is not tight enough. That’ll be an easy fix but, again, not in this weather.

One last thing that I got my hands on. Pure unobtanium!

Part 3540574 – Plate

The actual latch plate to the glovebox. Mine currently has a homemade version that, while functional, is janky as all get-out. Now I can put the actual for real part in. Remember what I said earlier about purism? There you are.