Engine/Transmission (1998.5 - 2002) 01 block into a 99 cps sensor?

[summitracer]

well we just put a 01 engine in my buddies 99 and realized there is no crank position sensor in the newer block do any of you know how to get around this problem everything else is done except the very front of the truck hope we don't have to pull it again

 

[bbecker]

I have a '02 sitting on a pallet to drop into my '99 and need an answer to that same question. Called Piers and they said that it might work to splice the wires from the crank sensor into the cam sensor for the pick up signal but they couldn't tell me for certain since they had never done it . I didn't want to swap engines and try on a "might work" only to pull the engine back out to swap cranks for a tone wheel. Since you already have the engine you might try that - that's the best answer I have been given.

 

[Fishin Guide]

What is this sensor needed for? Not trying to ask a stupid question, but how about a newer model ECM? Would that fix it?



If that's the case, maybe Marco can do a custom one for you?



I don't know what the crank trigger plugs into, but I am guessing you can get around this by swapping electronics.



just an idea.



Dave

 

[bbecker]

'98. 5-'99 had a tone wheel located on the crankshaft '01 '02 has a tone wheel on the camshaft. moved from crank to cam for reliability reasons I believe. Basically tells the ECM at what rpm your engine is turning and is also the tach pickup sensor.

 

[SnoKing]

Well a cam turns at half the speed of the crank, so there would most likely be an issue, unless the cam sensor is getting two pulses per rev. Marco should know! SNOKING

 

[bbecker]

Thats true the cam turns at half speed but if the cam tone wheel is 1/2 the diameter of the crank tone wheel with the same amount of teeth to pass by the sensor theoreticaly it should show the same the same voltage output to the ECM.

That's the biggest ? I have , If I knew for certain that it puts out the same voltage I would try it.

 

[SnoKing]

Thats true the cam turns at half speed but if the cam tone wheel is 1/2 the diameter of the crank tone wheel with the same amount of teeth to pass by the sensor theoreticaly it should show the same the same voltage output to the ECM.

That's the biggest ? I have , If I knew for certain that it puts out the same voltage I would try it.

If it is counting teeth then it is putting out pulses for the teeth, not a voltage level. Again Marco is probably the one that can answer it. If the crank sensor is reading the 159 teeth on the ring gear and the cam tone wheel has 159 teeth, then you will only get 79. 5 pulses per rev from a cam sensor. SNOKING

 

[bbecker]

I may be wrong but as I understand it as a tooth passes by the sensor it creates a pulse which is read by the ECM as voltage (i. e. 1000rpm-3 volts , 2000rpm-5 volts)

As far as tone wheel size if you have 60 teeth on a 6 inch wheel that would be one tooth for every 6 deg. of rotation , if you have 60 teeth on a 3 inch wheel that wold be two teeth for every 6 deg. of rotation. If you have twice the amount of teeth passing by the sensor at half the speed it should create the same amount of pulses so the ECM should sense the same voltage. I COULD BE WRONG

 

[summitracer]

well the truck runs we put the ecm off the 2001 on it but it doesn't run very good it won't hardly move if you floor it it kinda drives if you ease into the throttle the shifting is real strange the truck has twin turbos a high perf transmission and big sticks

 

[bbecker]

The crank sensor went bad on my '99 and had similar problems , like the infamous dead pedal and no tach . I was told that it would run but in a limp home mode due to no CPS input.

 

[Bulldog80]

I've been working on the exact same situation on a friend's truck for the past several months. No one seems to have an answer for this situation. I know that you will probably need the PCM from a 2001 also. All of the info. that was coming from the crank position sensor now needs to come from the cam position sensor. Am waiting for the right PCM to try with a different ECM flash. Hopefully this go round will work. It's certainly not been easy. I'd be interested in Marco's input too.

 

[summitracer]

yea we're using the 01 ecm it won't run with the 99 ecm i e-mailed Marco and told him to reply on here but I'm sure he's busy we were also told we needed the pcm out of a 2001 but we can't find one we wired the crank sensor into the cam sensor and the tach works but still runs in limp mode it just goes to idle at 2000 rpm no matter what we do

 

[summitracer]

we put the pcm out of my truck in it and it runs good now but won't shift out of first cause mine's a 6 speed and his is an auto so I guess we need to find an early 01 auto pcm anybody have one laying around? Thanks for the help so far, it looks like we might get it running right yet

 

[Marco]

Hi Gang,



Sorry, there's no simple solution for your problem.

Lemme see , where do I start here?



Ok, the 98. 5-2000 trucks used Cam & Crank sensors. From 01 and up only the cam sensor is used. That you already know...



Exactly WHAT has been changed? Obviously the sensors AND ALSO the engine harness! In the 01 and up engines the CAM sensor is wired to the ECM pins where the older truck had the Crank sensor . So when you swap an engine be aware that you need also the correct harness or you have to cut and solder wires.



Lookie here: http://www.dodgeram.org/tech/dsl/ECM/ecm.gif



As you can see, each of the cam and crank sensors use three wires.

If you have to cut them, you have to move them ALL! The ground circuits are two different beasts. If you don't move all the wires it won't work!!!



Before you swap the engine you could check if the 01 engine still has the tone wheel on the crank. The very early 01's still had the tone wheel on the crankshaft. That would make the swap easy... .



No tone wheel on the Crank? Welcome to the nightmare!

The tonewheel on the camshaft is not the same design as the crankshaft tonewheel! As you've already found out wiring the cam sensor into the crank sensor location on the ECM is not enough.



You will have to use the 01 ECM too, since only the 01 ECM is provided with the correct SW to read the cam tonewheel signal. At this point the engine will run but mostlikely in limp mode. That's because also the PCM needs the input from the cam or crank sensor... In other words you will need also the matching PCM.



Yet, now you could have still problems. The 01 engine uses a different software than the 01. 5 engine... You need the CORRECT ECM or you will have an engine that will never perform perfect!



From what I know, the 98. 5 and 01 PCM's can be swapped without any problem, except for the fact that you obviously need the correct PCM for the transmission in your truck ( AT / Stick ).



If instead you want to swap an 98. 5 to 00 engine into an 01 and up truck then the above is simply vice versa.



Helps some?



Marco

 

[jwernert]

We put an 02 motor into a 99 truck w/ a 5 speed. we swapped ECM, PCM, and the wiring harness. The truck runs great with no motor problems. The ABS and brake lights are on, and we think that is because of the CTM. The ABS does not work, but cruise and everything else does. The 02 was a HO 6 speed. The 99 was a 5 speed. Now the 99 is a 5 speed with a 02 HO motor. Hope this helps.

 

[Bulldog80]

Any further luck Summit? I'm still waiting for the other pcm to try. Let me know-

 

[summitracer]

yea it's running good to 2000 rpm now we found out the waste gate on the top turbo was stuck open we're waiting on the pcm to show up we were hoping to have it friday but it didn't show the owner is driving the truck everyday and it actually runs real good if you don't mind it shutting off at 2000 rpm he was at Cummins in Desmoines and when he left someone in a dodge pulled up next to him and smoked him out he was pretty bummed that he couldn't play but it shouldn't be long now we are planning to pull in Adel next Sunday