FAQ: Crankshaft Position Sensor (DTC P0336)

I'm doing this tomorrow, I'll try to grab some pics.

scratch that, I found my radiator leak and now I'm not sure if I'm going to repair this car or just sell it off.

For those that have been following this thread for some info on the special bolts and the extension to the center bolt of the Snap-On puller, I have been made aware of a complete kit (by Albertj) made by Lisle for less than just the bolt kit kit from Snap-On. So if someone is planning to do this job I highly recommend the Lisle kit as it is a complete puller and bolts, all ready to go.
If you already have a puller and don't want to buy another read below the link for another P/N for just the Lisle hardware kit.
Below is the link for the Complete Lisle Puller Kit.
I have purchased from This tool vendor in the past and they are good, with great prices, very good shipping times if the tool is in stock and if you already know the original Tool Mfg and Part number, you can search quick and get what you want fast.

http://www.tooltopia.com/lisle-45300.aspx?utm_source=googlebase&utm_medium=cse&utm_term=LIS45300&utm_campaign=googlebase_18u

Note: In the description of the complete kit it mentions you can buy Lisle #45350 Retrofit Kit, which I'm assuming is all the specially cut bolts and center adapter for $13.00 and change. So instead of buying the whole Kit if you already have a puller, made by any mfg, I would assume this kit of special fasteners and center extension would be a good addition for use on the 3800.

Yes you can use just 1/4-28 x 3 " Long bolts and washers, ( the snap-on bolts measured 2 15/16" from under bolt head to end) but that provides the opportunity to get the 4 finger part of the tool to become cocked at an angle and then damage the sensor or the pick-up tabs of the reluctor wheel on the back of the Harmonic Balancer.
If you mark the bolts and thread them into the Balancer 1/4 of an inch you will not have any problems as far as I can tell. The special bolts had the first shoulder right at 1/4", so that is as far as you could thread them in. That ensured enough thread engagement and that each bolt was threaded in the same amount and even. Now you just have to make sure you pull evenly on he Center stud and you can mitigate any damage. Now that I have seen the "Special Bolts" and the extension, I think I could do it another time without the kit.
But when I have another tool order for ToolTopia that will total over $99 (free shipping) then I will order #45350 (fastener Kit) because it's cheap enough with free shipping.

When I did mine I just used my regular hb puller with longer center bolt and I went to lowes and got the 1/4 bolts and it came right off.

I found this information to be very helpful and I'm planing on doing this test this weekend as I continue to have a intermittent problem with mine, when I go at highway speeds and hit a bump the Check Engine and the Traction Control off light comes on and then a few miles afterwards the engine stops.... and I have to let it cool down and then restart the engine, I suspect that it's a wiring or vibration problem related; the code I'm getting is P0336. but here is the article:

http://troubleshootmyvehicle.com/gm_ckp_3.8L/test_ckp_sensor_1.php

Matthew sounds like he had a heck of a problem there i hope u get it fixed soon. i think i have a similar problem to his however. my traction light stay on saying that traction is off. he person i got the car off of says its been on and he dosnt know why, but i dont think it can totally be good, especially constantly staying on you know. i wonder if matthews problem started out like mine? uh oh.

rk0ehn wrote:

I found this information to be very helpful and I'm planing on doing this test this weekend as I continue to have a intermittent problem with mine, when I go at highway speeds and hit a bump the Check Engine and the Traction Control off light comes on and then a few miles afterwards the engine stops.... and I have to let it cool down and then restart the engine, I suspect that it's a wiring or vibration problem related; the code I'm getting is P0336. but here is the article:

http://troubleshootmyvehicle.com/gm_ckp_3.8L/test_ckp_sensor_1.php

Yesterday I tested the CKP and here are the results:

3x signal:
ON - 6.63V
OFF - .04V

18x signal:
ON - 6.64V
OFF - .02V

Power from ICM to CKP: 11.00V

Ground from ICM to CKP: 12.35V

I also check for continuity for each signal cable, PWR and GND. Everything is O.K.
BUT, some sensors work different under certain circumstances; like vibration, heat (cold or hot), certain RPM, etc. so even mine tested alright... it still fails, what I would need to do is by the time the engine stalls or "does not start" I'll have to check at the connections again and see which one is NOT working or getting signal I know the sensor is not working "right" but until I get some money I'll still check it.

pattern I've seen on the Riv is the CKP fails "bad warm" and when you are trying to restart engine, can't get thru start sequence.

by the way have you wiggled your harmonic balancer? maybe sensor is good, signal is bad...

Albertj

that's what I thought as well, maybe the Harmonic balancer is somehow "bad", worm or something... but I can see it's pretty firm, I mean it doesn't wiggles or looks damaged, etc.

But I'm not sure how the "teeth" on the harmonic balancer are I am 99% the CKP is bad, I HAVE TO wait at least 2 min before I can start the car again I it fails of course, I mean not all the time but it is annoying. My local Autozone have one for $500.00 pesos about $37.03 dlls pretty expensive but I have to ask if it is the Delphi or ACdelco one. Rockauto.com sells a Delphi CKP for 28.99 + shipping.

rk0ehn wrote:

that's what I thought as well, maybe the Harmonic balancer is somehow "bad", worm or something... but I can see it's pretty firm, I mean it doesn't wiggles or looks damaged, etc.

But I'm not sure how the "teeth" on the harmonic balancer are I am 99% the CKP is bad, I HAVE TO wait at least 2 min before I can start the car again I it fails of course, I mean not all the time but it is annoying. My local Autozone have one for $500.00 pesos about $37.03 dlls pretty expensive but I have to ask if it is the Delphi or ACdelco one. Rockauto.com sells a Delphi CKP for 28.99 + shipping.

The Autozone one is probably the Standard or Standard T_Series CKP. The Delphi CKP for $29 from rockauto.com sounds good.

teeth on the HB never break or wear unless physically damaged... eventually the rubber wears out and the HB must be replaced... if you are flush with cash it is not a bad idea to think about getting a replacement HB for maintenance (keep the old one) when you replace the front main seal. When you pull the HB to do the seal look at the rubber in the HB and if it is starting to dry out or crack at all then replace it.

Rickw wrote:

the Harmonic Balancer is indeed a Torque to Yield and the P/N 24504736 is available for $7.96.

Where else can I get this bolt??

Thnx

rk0ehn wrote:

Rickw wrote:

the Harmonic Balancer is indeed a Torque to Yield and the P/N 24504736 is available for $7.96.

Where else can I get this bolt??

Thnx

I think you are in a worst case scenario. Yes it's a TTY bolt and _shouldn't_ be reused, but I've seen them reused many many many times with no problems. In an ideal situation you get a new one. If you are stuck just reuse and you'll be okay.

Good luck!

rk0ehn wrote:

Rickw wrote:

the Harmonic Balancer is indeed a Torque to Yield and the P/N 24504736 is available for $7.96.

Where else can I get this bolt??

Thnx

Almost any GM dealer (not just Buick) - also you may be able to get a dealer to give you the spec for the bolt (usually the specs are available) and buy the bolt elsewhere. Would not surprise me to find it through a NAPA although I admit I have not tried.

For your model Riv also be sure to get a new woodruff key for the HB and a repair sleeve if you need it - see rockauto.com for example...

Albertj

Thanks guys

I was thinking on getting another bolt with the same specs

according to this website the specs for the HB bolt part number 24504736 (126 in the index number) are: 3/4-16X3

Can anybody tell me how do I read this numbers? so I can buy the bolt please

http://parts.nalleygmc.com/showAssembly.aspx?ukey_assembly=368613&ukey_make=1022&ukey_model=14451&modelYear=1996&ukey_category=19398&ukey_driveLine=0&ukey_TrimLevel=0&ukey_modelRange=0&searchString=

And the 128 index number is the "key" for the HB (P/N 12563282), although I don't think rockauto.com sells this part even with a part # search

My problem is that my father is the one that can go to El Paso, TX where he has his U.S. address for "online shopping" (he lives here in Juarez, Mexico as well) and he only buys parts in Rockauto.com because he doesn't "trust" shopping online....

I have never buy Parts here in Mexico from the GM dealer, but hey there is always a first time.. but that will be my last resource if I can't use the same bolt or find another bolt with the same specs

3/4-16X3 means the shank (threaded part) is 3/4" diameter, has 16 threads per inch, and is 3" long below the head.

GREAT Thanks!

Make sure you match the grade of the bolt exactly, and follow the torquing procedure when installing.

If you are going to replace the bolt, get it from GM.

rk0ehn wrote:

....I have to let it cool down and then restart the engine

OK well I haven't change it yet, but I'm posting this in case someone else has a problem like mine. Since I changed my thermostat and the old one was stuck open, the engine was taking longer to "warm up", now it warms up faster and getting a better mpg, but the engine compartment is getting hot quicker so when I drive the car until it reaches about 190*/200*F and turn off the engine, it will not restart unless I let it cool down.... but from 200*F until 140*F it takes about 1 hour just to let the CKP cool off enough to restart the car, so my wife came up with the idea of just throwing 1 or 2 glasses of water and try to start the engine... well let me tell you that it worked PERFECTLY. I mean i know I have to change it but from waiting 1/2 to 1 our to let it cool down by itself, just cool it quicker with water and after doing so the car will start right away, but make sure you don't have and wires open and the connections are tight. I hope this will aid someone.

rk0ehn wrote:

rk0ehn wrote:

....I have to let it cool down and then restart the engine

OK well I haven't change it yet, but I'm posting this in case someone else has a problem like mine. Since I changed my thermostat and the old one was stuck open, the engine was taking longer to "warm up", now it warms up faster and getting a better mpg, but the engine compartment is getting hot quicker so when I drive the car until it reaches about 190*/200*F and turn off the engine, it will not restart unless I let it cool down.... but from 200*F until 140*F it takes about 1 hour just to let the CKP cool off enough to restart the car, so my wife came up with the idea of just throwing 1 or 2 glasses of water and try to start the engine... well let me tell you that it worked PERFECTLY. I mean i know I have to change it but from waiting 1/2 to 1 our to let it cool down by itself, just cool it quicker with water and after doing so the car will start right away, but make sure you don't have and wires open and the connections are tight. I hope this will aid someone.

sounds like you have a crank sensor that died. While you have the HB off please replace the crank sensor. Get one from GM (around $85 US maybe less) or from rockauto.com (lots less $$)

Albertj

Hello again.
Today we got a check engine light, so we had it ran. It came up with the above error. Can someone post some pics on how to get to the harness so we can check it?

matt270avian wrote:

Hello again.
Today we got a check engine light, so we had it ran. It came up with the above error. Can someone post some pics on how to get to the harness so we can check it?

Its behind the harmonic balancer. Here is a picture of the timing cover with the balancer and water pump removed. The CPS is directly to the right of the crankshaft.

Just replaced the second crank sensor on mine a couple of weeks ago. I didn`t think they wore out but apparently magnets do. Nothing is made to last a long time any more.

Weez wrote:

Just replaced the second crank sensor on mine a couple of weeks ago. I didn`t think they wore out but apparently magnets do. Nothing is made to last a long time any more.

Crank sensor is not a magnetic, is a hall-effect sensor. It senses the teeth behind the balancer. What happens is the internal connectors fail electrically due to heat cycling. If you bought a "cheap" one (under say $40 on rockauto) they are not connectorized the same way internally as the better (Delphi, ACDelco) ones, and they fail in ~2 years or so. My mechanic quit putting the cheap ones in for that very reason. Even if it's only just this once get a **good** one, you'll be happier.

Got 7 years out of the original. 8 years out of the next one. I`m pretty sure the newest one is a GM product. Any ferrous steel sticks to this thing like glue. There are magnet(s) in this thing. JMO