is it a nightmare to change crank position sensor?

[no_doz]

im looking to get my buddies 92 z34 but it just one day quit getting spark, everything else works as it should, but it wont run & it just flat out doesnt get spark & ive had a couple of you tell me that its more than likely going to be the crank position sensor (which wouldnt surprise me because i had the same thing in a 96 lumina & it had the EXACT same symptoms). my question to you guys now is, how hard is it to replace this sensor? i know doing rear plugs on these sucks,how bad is the sensor?

[Superdave]

you do it from underneath, it just all depends on how much crap is in the way.

Try soaking the area around it in PB blaster and spinning it around a bit, be gentle because if it breaks off you'll have to pull the pan.

[IsaacHayes]

On my car, with the 4T60-E huge auto I reached around the control arm, and another time through the tie rod area.

[no_doz]

but on a 1st gen z34 how hard is it

[1988GTU]

IIRC it is a PITFA to do let alone get at the plug for it. I think you need to take out the alt to even remotely get at it.

[no_doz]

what are you smoking? that has nothing to do with anything in this thread...

[IsaacHayes]

Should be on the back of the block right? That's how mine is on the 3100. Should be the same, just reach and feel for it, 10mm deep socket on a 1/4" ratchet, or small extension and normal socket. Alt is not gonna be on the back of the block on a LQ1 is it? I know they are down low but they are probably on the front not between the firewall right?

You gotta just get in there and feel for it. That's the only way I got to it. I could not see it with my huge transmission in the way. I took the wiring harness off, bolt off, and then twisted it back and forth as I wiggled it out. You gotta have strong fingers and keep wiggling/twisting to get it to come out.

[GTP091]

im looking to get my buddies 92 z34 but it just one day quit getting spark, everything else works as it should, but it wont run & it just flat out doesnt get spark & ive had a couple of you tell me that its more than likely going to be the crank position sensor (which wouldnt surprise me because i had the same thing in a 96 lumina & it had the EXACT same symptoms). my question to you guys now is, how hard is it to replace this sensor? i know doing rear plugs on these sucks,how bad is the sensor?

Go at it from underneath. Don't pull the alternator, that guy probably works for GM... Jack the car up put blocks or jack stands under it so you have almost two feet clearance. Use a trouble light and you can get it no problem. Having the right tools makes it a snap. The first time I tried to get my hand in there I was about 8 inches from it, very tight; and I did swear alot then I thought it through and went to the hardware store. get a 10mm box ratchet wrench and black tape it to a real long wrench very tightly. When I did mine I used some very long alligator pliers (24") with locking handles to remove and reattach the plug. made it a breeze. A can of brake cleaner makes it all easy to see. piece of piss...

[bszopi]

Alt is not gonna be on the back of the block on a LQ1 is it? I know they are down low but they are probably on the front not between the firewall right?

That is exactly where it is at - bottom, back of the block. Yeah, real crappy design.

[IsaacHayes]

Hmm, GM must have used a BFH to make room in the firewall there LOL. How would it even fit on a 4T60-e car? LOL

[Dave96z34]

What sensor was he asking about the one on the side of the block or the one under the dampener?

[1988GTU]

I stick with what I said. I dont work for a dealer (not anymore) and even if I did what does that matter?

My only disclaimer is, I am referring to the 94+ style. The BOOK says it like this:

3X CRANKSHAFT POSITION (CKP) SENSOR

1. Disconnect the negative battery cable.
2. Raise and safely support the vehicle.
3. Remove the intermediate exhaust pipe.
4. Remove the rack and pinion heat shield.
5. Remove the alternator cooling duct.
6. Detach the sensor electric connector.
7. Remove the 3X CKP sensor from the engine.
8. Inspect the sensor O-ring for damage, and replace, if necessary.


That way is wrong and doesn't work for me.

[savannaz34]

you dont have to remove shit.except for the crank sensor itself,it is located on the right side of the block{back)just above the oil pan edge,lift the car(aproxx 2 feet) as said before in this thread.look between the engine and tranny,you will see the knock sensor,block heater,and of course the crank sensor,now,i personaly got at it from the tunnel where the exhaust pipe runs to the back,reach over the rack and the tranny,and you should still be able to see the sensor while your hand is in there(laying on the ground,feet towards right rear tire)use a short 1/4'ratchet and extention to removve the bolt.you dont need long pliers to remove it.you can use short pair too if you can reach(its easier as there is not much room to angle the pliers)most definetly spray it with carb cleaner or similar substance to make it easier to remove.i have broke one on my 2nd z34,and is not fun at all,hope this helps.
also for the knock sensor,go at it the same way with a deep 7/8 socket,2 8' extensionswith a swivel in between the two extesions.

for all of you that work for dealers,dont feel bad,ITS NOT YOUR FAULT YOU HAVE TO DO EVERYTHING THE EASY AND TIME CONSUMING WAY,
the funniest one is the amount of time the dealer wants to change the oil pump drive o-ring LOLOL

[pocket-rocket]

Hmm, GM must have used a BFH to make room in the firewall there LOL. How would it even fit on a 4T60-e car? LOL

I know this is an old post, but you don't need a BFH to fit it in there. It never touches or comes close to the firewall either. It sits above the diff cover on the 4T60-e. I used to remove an axle/hub as one piece to get the alt. out from the wheel well, vs the other way to do it which was dropping that side of the subframe, which is the same way I would go about getting at a CPS sensor on an auto car.

[pocket-rocket]

for all of you that work for dealers,dont feel bad,ITS NOT YOUR FAULT YOU HAVE TO DO EVERYTHING THE EASY AND TIME CONSUMING WAY,
the funniest one is the amount of time the dealer wants to change the oil pump drive o-ring LOLOL

How about the one I heard before... $600 for an alternator change. I just posted above how I do it and IIRC, I have it down to an hour-hour and a half job working at a relaxed pace.