Engine/Transmission (1998.5 - 2002) Crank sensor failure... Help please...

[Sean Flanagan]

I have this posted in the 911 forum here: https://www.turbodieselregister.com/forums/showthread.php?p=1705062&posted=1#post1705062



I'm putting the link in this forum for greater visibility. Any input is greatly appreciated. At this point I am looking for a good shop, or individual in the Denver area that can do my dirty work...



The TDR is excellent! Thank you for your help.



Thanks,



Sean

 

[Cummins724]

They aren't hard to change..... just drop the starter & its toast.

 

[Brand-X]

The job is not bad I have one if you are interested I missplaced mine bought a new one and found the first one before the second arived :-laf PM or email me if intersted... George

 

[Joe Mc]

Only thing to be careful of is removing the old one. Be patient and wiggle it alot, in and out, side to side as you pull dont try spining it out, you'll break something off and then be royal. Definitly remove the starter - ah, don't forget to disconect both batteries . . .

 

[Sean Flanagan]

Hi Guys,



I already changed the sensor. In the 911 post I refer to this. I guess I should have reposted the whole saga here. Sorry for the confusion.



So here is the "Cliff Notes version"

1. Before I replaced the sensor it didn't run at all.
   
2. The old sensor had the sensing surface sheared off.
   
3. I replaced the sensor, I still get the trouble code and the engine is in limp mode.
   
4. I reset the codes with a scan tool, restart, the tach works for about 10 seconds, then goes to zero, then "Check Engine" comes back on. Engine is running but in "Limp Mode".
   
5. I check the codes again and get the P0336, indicating crank sensor failure. I repeat steps 4 and 5 several times...
   
6. According to some people in the 911 forum, there is a chance that the tone wheel on the crank has come loose.
   
7. This repari involves dropping the oil pan and potentially the crankshaft. That is the part I do not want to deal with myself.
   

If anybody has any other ideas, It would be greatly appreciated.



Does anybody know how to test for this tone wheel failure without dropping the pan?



Does anybody know a reputable shop or individual in the Denver area that doesn't cost an arm and a leg.



Thanks,



Sean

 

[socalmat]

I know nothing, let alone about your crank sensor. But I have trouble shot many things in life and it may be true here. It is usally something simple that let go. Would there be an electrical connection someplace that needs to be pushed together?

 

[obert]

If the sensor was sheared, something hit it. Scince the engine is still running I would haveto presume it was the tone ring flying off the crank.



If you want to pull the starter and sensor again, you could wiggle your head up in there to look inside the sensor hole and see for shure.

 

[Sean Flanagan]

I Borrowed a borescope and took a peek inside...



The tone wheel is partially missing and what is still there has missing teeth.



The worst part is that now I see that it caused a crack in the block on the passenger side, right where the tone wheel is... or was.



What the heck can make this thing come off. When it happened I was just putting along at about 40mph.



Pictures here...



https://www.turbodieselregister.com/forums/showpost.php?p=1705458&postcount=15

 

[wtfd6]

the bolts arent torqued very tight. 27 inch pounds if I remember correctly. I dont know if they didnt put good thread locker on them when they were built or what.

 

[Bulldog80]

The cracked block is obviously a huge problem. As far as the rest of the driveability issues, you can wire the crank position sensor into the cam position sensor and it will run fine. At least you wouldn't have to replace the tone wheel that way.

 

[wtfd6]

my pan was full of metal when mine broke. I will post a picture as soon as I find it.