Cadillac Owners Forum banner

1 - 5 of 5 Posts

·
Registered
2005 Pontiac Bonneville GXP (4.6L 32-valve Northstar)
Joined
·
3 Posts
Discussion Starter #1
Greetings! I'm resurrecting this thread (I apologize!) and reaching out because of the well-written post by AJxtcMan about replacing the crankshaft position sensors. I have a 2005 Pontiac Bonneville GXP, which has the 4.6L 32-valve Northstar motor. I need to replace my crankshaft position sensors and I was looking for a little more help than I've found in my search. I've compared the instructions here with those provided by alldatadiy.com, and I've reached an impasse: How do I physically get to the sensors to remove and install them? Underneath and reach up? Remove front bumper cover and reach in from the front? I could not see a path that would give me sufficient space to reach through to the sensors.

According to alldatadiy.com:
  • Raise and support the vehicle. Refer to Vehicle Lifting.
  • Remove the air deflector.
  • Remove the oil filter adaptor.
  • Disconnect the crankshaft position sensor electrical connector.
  • Remove the crankshaft sensor retaining bolt.
  • Remove the crankshaft sensor.
I got as far as removing the air dam, and when I got back underneath the car, I could see the oil filter and the oil cooler lines, among others. I could not fit more than a finger or two in there. The front motor mount and frame are immediately in front of the oil filter and adapter. How do I get physical access to the sensors? While I'm replacing these sensors, I am also planning on replacing the oil pressure switch as the dash gage no longer works. I suspect that it was damaged by leaked oil that also damaged the crankshaft position sensors when the intake manifold gasket gave out.

While I was under the car, I noticed that one of my oil cooler lines did not have the retaining clip cover in place. Needless to say, the bottom of my engine is pretty messy from oil.

A couple of other questions I have come up with during this process:
  • Do I need to or is it recommended to drain my oil?
  • Should I replace the oil cooler line adapters if they appear to be leaking?
  • Is removing the oil filter adapter really necessary in this process?
  • I've seen other forum posts that talk of removing the harmonic balancer to get access to the sensors from the passenger side of the engine - would this be a useful approach?
I greatly appreciate any guidance and advice anyone could share! Pictures would be a bonus!
Thanks in advance!
Greg
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
69,900 Posts
Moved from Tech Tips to the Northstar forum.

For our Seville/Deville cars we drop the lower air deflector and oil filter adapter and work from underneath > up. Takes wobble sockets and patience. No idea of what your physical arrangement is. The CKPs are nowhere near the harmonic balancer. Regardless, the work is tedious and in very tight quarters.

Curiously, Alldata and other service manuals assume that all other interference is removed prior to beginning a specific repair/replacement. I would hate to think that the Pontiac required powertrain cradle dropping to get to the CKPs.

CKP-Oil pressure and level.jpg


Anything in these links ? pontiac forums.com - Google Search
 

·
Registered
2005 Pontiac Bonneville GXP (4.6L 32-valve Northstar)
Joined
·
3 Posts
Discussion Starter #3
Moved from Tech Tips to the Northstar forum.

For our Seville/Deville cars we drop the lower air deflector and oil filter adapter and work from underneath > up. Takes wobble sockets and patience. No idea of what your physical arrangement is. The CKPs are nowhere near the harmonic balancer. Regardless, the work is tedious and in very tight quarters.

Curiously, Alldata and other service manuals assume that all other interference is removed prior to beginning a specific repair/replacement. I would hate to think that the Pontiac required powertrain cradle dropping to get to the CKPs.

Anything in these links ? pontiac forums.com - Google Search
My apologies for not responding sooner! I never received a notification of any replies, which I was expecting to have received. Ironically, I started out from the Pontiac Bonneville forums and ended up here as a result of links from another similar post that referenced the AJxtcman post. From what I saw underneath the engine, I can't imagine a way physically to get my hands, much less any part of my arm up past the lower part of the cradle. Would you think it possible to access from the front if the bumper cover were removed? I do have a few wobble socket adapters, and I had seen other references to needing use of them.

By way of the harmonic balancer, I was skeptical of that approach. I wonder if it was a method more applicable to non-Northstar motors?

As of this posting, I have not re-attached the lower air deflector yet (need to replace a few of the plastic connectors anyway), so I still have access if I can find a way at it. The only problems I've faced so far have been the need to occasionally turn the key to start twice. First time the engine doesn't know what the position of the crankshaft is in, and the second time it fires up.

I appreciate the assistance!

Thanks!
 

·
Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
Joined
·
69,900 Posts
The plastic rivets can be found on the HELP! racks at parts stores, at a Fastenal store, or in the AuVeCo fasteners catalog.

If one or both CKPs have failed then the engine ignition timing defaults to a fixed 10 degrees BTDC and anywhere off-idle the engine will lack life and performance.
 

·
Registered
2005 Pontiac Bonneville GXP (4.6L 32-valve Northstar)
Joined
·
3 Posts
Discussion Starter #5
The plastic rivets can be found on the HELP! racks at parts stores, at a Fastenal store, or in the AuVeCo fasteners catalog.

If one or both CKPs have failed then the engine ignition timing defaults to a fixed 10 degrees BTDC and anywhere off-idle the engine will lack life and performance.
I figured as much on the rivets, and as the performance goes, it doesn't get the best mileage-to-gallon ratio right now! :poop:It probably needs a host of sensors replaced, not the least of which being the HO2 sensors, which I just won't even attempt! I have no wish, desire, or the necesssary tools and knowledge to lower the engine 3 inches to replace the rear sensor.
 
1 - 5 of 5 Posts
Top