This how-to will attempt to illustrate how to replace your crank position sensor. This sensor seems to be a somewhat common problem here and on the cobalt forums. My car would die once it got hot, and would not restart until it cooled down. It was throwing the codes P0335 and P0336. Replacing this sensor fixed this problem.
Doing this job yourself can save you some money. The sensor itself is only $15 (around $30 after s&h) from GmPartsDirect.com (part number 12789959). Supposedly, you have to have a crank variance relearn (sometimes referred to as a case relearn) once this sensor is replaced, but I did not have to have this done.
- 13mm wrench
- 13mm socket
- Vice grips
- 15mm socket
- 10mm socket
- New crank sensor
I began by disconnecting the visible hose from the nose of the intercooler pump (the pump is next to front engine mount under the car) and letting the coolant drain into a small clean bucket(so you can reuse it). I found that using a pair of vice grips to hold the hose clamps open while you try to loosen the hose from the pump made life easier. Push the hose up and towards the driver’s side, out of the way.
I then unbolted the intercooler “reservoir” up top, and disconnected both of the hoses from the endplate (on the side of the intake manifold) using the same method.
Next is removing the pump itself. First, unplug it. There’s a bolt in the top of the clamp, and the bottom, the bottom one I used a 13mm wrench because a socket wouldn’t fit between it and the subframe, but for the top one, you can use a standard ratchet and 13mm socket. Take the clamp off once unbolted, and push the pump toward the passenger side until it is clear of its mount, and pull it down, bringing with it the top hose.
Now, using the 13mm socket, unbolt and remove the intercooler pump mount. There are 3 bolts in it.
Now you shouldn’t have any problem getting to the bottom starter bolt with the 15mm socket, and the top one should be accessible through the hole you made by disconnecting the intercooler reservoir hose up top. It’s a bit of a pain, but you can get it.
The bottom bolt and the top bolts are shown in the pictures below, respectively.
With the bolts out, the starter should be free to pull out of the transmission, but I had to clip a couple of wire ties to let it move enough to pull it out and set it out of the way on top of the subframe. You should now have a pretty clear view of the knock sensor (the wires that look like they just go to a bolt, not shown) and the crank position sensor, as shown below.
Remove the 10mm bolt securing the sensor, and twist and pull the sensor out of the block. This is what it looks like:
Now do everything you just did, but in reverse. I would recommend starting the car once you get the starter back on, to see if it’s working and if your problem is solved. Once everything looks alright, put your pump back on and refill, bleed, etc. If it is throwing codes, get it to a dealership to get a case relearn. You should be able to drive it there without issue (from what I’ve been told).
Hope this was helpful. If you have any questions, let me know!