Engine/Transmission (1998.5 - 2002) Crank Sensor

[BHerndon]

My 99 Duelly with 235 CTD started to do a momentary jerk like you had cut the Ign. Switch off and back on real fast. It has no set time to do it-only when it wants to. It don't matter if it is loaded or not. We where pulling a 20' Haulin Car Hauler. We had to go from Al. to Co. and back to pick up my wife's bike and it started this on the way out there. After we got back-I carried it to a local Diesel Mechanic I know and he run a scan on the truck. He said it was the Crank Sensor Code that showed on his scanner.



My Question Is--Is there any way to test the Crank Sensor to see if it is really bad or if it could have been a loose connection that caused the jerks and the Code to be set? If anyone has had this same problem-Please let me know what you did to check it and to fix it.



THANKS::BHerndon

 

[JFaughn]

Witch crank code was it , theres more than one , the best tool is a dig. graphing scope , most shops should have one , some times a little metalic dust can get in there -freaks out the sensor kinda, the connector can get dirty [ contact cleaner {plastic safe}] , wire to or from computor .
Just some starting points .

 

[BHerndon]

Thanks John::I found 5 trouble codes in my Ram Service Manual that could have set the code. I don't remember the number of the code in my truck. He erased the code with his Snap-On Scanner and let my truck run for about 45 minutes with the scanner hooked up to the truck. It did not set the code again during this time. He told me that the computer lost it's signal from the sensor so it tried to catch the engine up. This is why it jerked he said. I took the starter off and checked for a loosconnectionon and corrosion and everything appeared alright. I went ahead and replaced the sensor while the starter was off. I was hoping I could check this sensor some way just to see if it is bad. If not-then I would keep it for a spare. The codes I found are--PO320 (M)--PO325--PO336 (M)--PO 387 and PO388. I think the code was the PO 388 but I not sure. If you know of a way to check it off the truck--Please let me know.



Thanks::BHerndon

1990 Duelly 160 HP CTD Auto all Original Miles Unknown--1999 Quad Cab Dually 235 HP 5 speed 354 rear--All Original except for a 63 HP TST. 69,??? Miles and Climbing.

 

[JFaughn]

The tricky part is there are checks & then there are checks , the only check that I would suggest is that has the highest % of chatching a problum , thats what I said earlyer , a digital graphing scope , any thing less can miss a slitly bad signal , witch is enough to cause a problum , but it has to be inplace to create a sig. , there are tests for off the truck but again they are limited ,
To check , remont , eng. spinning , meter mentioned above .
With the new sensor , has the problum gone away .

 

[BHerndon]

I have only driven the truck about 60 miles since the new one but the light has not come back on yet. Everything seems to be working normal. I quess time will tell-If the light comes back on shortly then we can assume the problem was not in the sensor. I forgot to say that this sensor was replaced one time under factory warranty. This may be a common problem with this year truck.



Thanks for trying to help. If it happens again-I will try to find someone that has this kind of scanner.



BHerndon:: Oo.

 

[Mr. C]

I just replaced the crankshaft position sensor on my 99, it threw a P0366 code. It still ran but the tach was dead for a bit untill the computer figured out where everything was again. It would run very rough at an idle when the tach was dead. I don't think there is anything that can be done to repair a bad sensor, it is a hall-effect signal generator if I'm not mistaken. It's only $45 or so, I'm gonna cut my old one open to see what's inside.

 

[BHerndon]

Thanks Mike::Let me know what you find out with the sensor. I see where you are running Bio-Diesel. How is it working out and how expensive is it to get started making it. This has been of interest to me since diesel started going up so high. This may be something I may want to do. Diesel Fuel here costs $2. 45 + a gallon now.



Again Thanks ::BHerndon