Crank, no start after replacing 2 CKP sensors- Fuel issue?

[gsr46r]

Hi all,

My 2000 ram 2500 cranked, but would not start. I managed to get it started and it got me home, but the tachometer said 0 for the whole ride.

I scanned it and got p0336 which is a crankshaft position sensor fault. I put a new one in (from rock auto), cleared the code, and when I went to start it, same problem- The starter cranks, but no start. The RPM's stayed at zero when it was cranking.

 

I haven't had great luck with rock auto, so i bought a CKP sensor from advance auto with a lifetime warranty. Put it in, tried to start it and the same exact problem! it cranks but does not start. At this point, i figured it's an electrical issue, so I ran a whole series of voltage and resistance tests. Appreciate the detailed code information!  Each of the 3 parts of the sensor produced voltage or completed a circuit.

 

When i connected A to C (sensor to ecm signal wire), the lift pump turned on. The middle wire B on the connector (on a hall effect sensor) had a lot of resistance from the CKP sensor connector to ECM connector, so I replaced it, and again, the same issue! It cranks but doesn't start.

 

I just got the batteries a couple weeks ago- I've tested them and know they're good. I am stuck and can't figure out what else the issue could be.

I am wondering if:
-for some crazy reason, i got 2 bad brand new sensors?

 

-maybe one of the female connectors doesn't meet the male pins? they sell a part at autozone i can buy to replace the CKP sensor connector

 

-let's say it's not an electrical issue, maybe an issue with the lift pump not sucking enough fuel? when the sensor is disconnected, i can turn the lift pump on manually by connecting A and C from the hall effect sensor. But, when the sensor is in there, i hear the lift pump turn on intermittently, like there is a reset period. but it's not loud like my 3rd gen. in my 3rd gen, any time i turn the key to run, i hear the fuel pump humming loudly from the tank

I've read about this issue and see most people have their issue fixed after replacing a CKP sensor or two. I haven't been so lucky lol.

Please give me your opinion. Could it be an issue in the fuel system? While it ran, the truck drove fine- nothing felt erratic

 

Thanks!

[gsr46r]

Anyone? Trying to get the truck running this week.

[kzimmer]

On 1/11/2020 at 9:17 PM, gsr46r said:

When i connected A to C (sensor to ecm signal wire), the lift pump turned on.

 

I don't have a diagram in front of me, but did you short the +5v wire to the ECM input? Not sure if this is a good idea, but I'm guessing it made the ECM thing the truck was running and ran the lift pump because of that.

 

On 1/11/2020 at 9:17 PM, gsr46r said:

But, when the sensor is in there, i hear the lift pump turn on intermittently, like there is a reset period.

 

When you turn the key on, you should here the lift pump for a couple seconds while it primes. That's normal. I think the key has to be off for 30 seconds to repeat that.

 

I wish I could help more than that. You may want to tap into the sensor wires and test the sensor input while cranking? 

 

[Great work!]

With the sensor out of the hole and plugged into its connector turn on key and have a helper watch the tach. Rub / wave a small screwdriver or metal object over the end of the sensor briskly if the tach bounces around or you hear relays click and other signs of life it's probably good. Use a camera  or mirror  to peek in the hole make sure the tooth wheel is there and turns with the crank

[dripley]

We did have someone on here a little while back that had the tone wheel on the crank malfunction in some way. He did have to replace that tone wheel IIRC.

[gsr46r]

Thank you all for the responses!

 

Made a dent in the diagnosis/repair last night. I picked up the mechanic from my job, and we took out the crankshaft position sensor. I stuck a socket extension in the hole, and the tone wheel rotates. There is no play in it back and forth.

 

Afterwards, reconnected the starter sans the sensor and I oscillated a wrench in front of the sensor as the mechanic tried to start the truck. As soon as I put the wrench in front of the sensor, I heard the lift pump turn on. Thus, this eliminates a bad sensor or bad wiring as a source of the problem. Truck still didn't start.

 

After we tested this, we removed the ECM. I am going to bring it into cummins today for them to look at it.  I also will put in a new camshaft position sensor in case its the culprit.

 

As far as I can tell, the wiring is good. There were no visible parts that are messed up.

 

Do I need to check the body grounds? They all seem tight to me, but I didn't voltage test them

[kzimmer]

34 minutes ago, gsr46r said:

After we tested this, we removed the ECM. I am going to bring it into cummins today for them to look at it.  I also will put in a new camshaft position sensor in case its the culprit.

 

Guys around here have mentioned that Cummins does not repair ECM's, and they do not have new ones. There is an article on this site with some recommended rebuilders, like Auto Computer Specialists.

[dripley]

4 hours ago, gsr46r said:

Made a dent in the diagnosis/repair last night. I picked up the mechanic from my job, and we took out the crankshaft position sensor. I stuck a socket extension in the hole, and the tone wheel rotates. There is no play in it back and forth.

 

Do you mean the tone wheel rotates on the crank or did you turn it with the starter? It should rotate with the crankshaft. 

[gsr46r]

Well, I got the verdict back from cummins. ECM is bad- it doesn't communicate. I'm glad I know what the problem is now- I'll look at the rebuilders. Cummins wants $2,900 for a new one, which is more than I paid for the truck lol. Do you have to send them the old one?

 

I couldn't tell if the crankshaft was rotating. The gear inside, in front of the sensor hole rotates- not a lot of resistance.

Can you link the ECM companies please? Can't find it on the site

 

 

Also, on the repair estimate it says Diagnostic Charge: $345. They're not expecting me to pay $345 for telling me it doesn't communicate?

[Dieselfuture]

2 hours ago, gsr46r said:

The gear inside, in front of the sensor hole rotates- not a lot of resistance.

That is your problem. I would first fix that before I did anything with ECM, it's a known fact cummins people are retarded, there are few at each shop that know what they're doing and that's what keeps them going, most of them have no clue. Fix the tone ring, it should not rotate freely, it should only turn when crankshaft is turning. Also get a new mechanic if he thought that was normal he doesn't know what he's doing doing either.

Once you fix that and it still does not work you need to check all your wiring and grounds. Once you get it running you also need to check your alternator for AC noise and do WT mod to prevent future electronic failures.

[dripley]

I have to agree with @Dieselfuture. The tone ring should rotate with the crank. If you can turn it with little resistance it may have come loose from the crank. If so your good crank sensor is not seeing spin as it should. I darn sure would not give up on the ECM yet.

 

You will have to send the old ecm in for a rebuild or pay a premium for no core.

[gsr46r]

Interesting. Let me make sure I'm getting this right. Since the tone wheel is connected to the crankshaft, it should be very difficult if not impossible to rotate with a screwdriver through the sensor hole?

 

I saw it- It looks like a big gear. Thank you for the feedback- The tone wheel being loose would def explain the code.

 

Regarding cummins, I didn't get a chance to meet the service guy, other than he must think I'm retarded- He sent me a bill for $220 to plug the ecm in and tell me its bad. I'm gonna raise major hell to get it back without paying, as I was told I would pay if there's an actual repair done. If the tone wheel's bad, the ecm report was a misdiagnosis.

 

I did have a chance to meet the part people who I found were quite stupid. Or at the least unqualified. He couldn't find a part without the engine serial no. so I looked on a random diesel parts website and got him the number so he could sell it to me.

 

If I adjust the motor mounts, can I remove the oil pan without removing the transmission?

[dripley]

Pretty sure you have to lift the motor to remove the oil pan.

 

Something bugging me about the tone spinning is that it is 2 pieces. If the screws holding it sheared or backed off one of the pieces would be pan. The other piece should fall off the crank also. Just seems odd.

[Dieselfuture]

48 minutes ago, gsr46r said:

Interesting. Let me make sure I'm getting this right. Since the tone wheel is connected to the crankshaft, it should be very difficult if not impossible to rotate with a screwdriver through the sensor hole?

It should be solid with crank, this is how computer knows piston is in certain position so it can command to inject fuel at the right time. If this gear rotates then fuel is injected at wrong time and engine will not run. If that ring spins freely then it will not start at all. It's not that hard to fix, just need to drop oil pan and few other things. There is a post here of it being done.

 

52 minutes ago, gsr46r said:

Regarding cummins, I didn't get a chance to meet the service guy, other than he must think I'm retarded- He sent me a bill for $220 to plug the ecm in and tell me its bad. I'm gonna raise major hell to get it back without paying, as I was told I would pay if there's an actual repair done.

I would if I were you especially if he said that. it's not unusual for a bigger outfit to charge that just to look at something. This is why we're all here trying to save each other time and money. 

 

56 minutes ago, gsr46r said:

If the tone wheel's bad, the ecm report was a misdiagnosis.

No not necessary, it can still have issues. What we're trying to say is you need to fix an obvious issue with tone ring on crankshaft being lose before you spend money on anything else. 

 

58 minutes ago, gsr46r said:

If I adjust the motor mounts, can I remove the oil pan without removing the transmission?

It's tight but can be done. You can lift the the motor up a little when you disconnect the mounts to gain more room.

[gsr46r]

Thank y'all again for helping me. I am gonna have my gf spin the crank when I check the tone ring.

 

I've been looking for an excuse to get an engine crane, so I guess I'll get one to lift the engine up a bit after I confirm the tone wheel is whack. Hoping I'll be able to get the pan off saturday. Will post updates.

[Dieselfuture]

You shouldn't have to turn the crank to see if the tone ring is bad, can you rotate it with a flat screwdriver with engine off. Because that's the assumption I'm making based on your post where your mechanic and you did this.  " I stuck a socket extension in the hole, and the tone wheel rotates"

[dripley]

If it moves freely with anything there is a problem. The ring is a attached to the crank shaft and should only move if the crankshaft does. 

[gsr46r]

Yes, I can rotate it with a screwdriver. I did with a 1/4" socket extension.

 

Sounds good- I just like to practice before I do the repair. I've read you have to rotate the crankshaft to remove the tone wheel, so I wanted to make sure I know how to do it. I have no prob working on other people's stuff, but get nervous doing my own stuff. But, if I don't fix this, the truck's just gonna sit. 

 

Man, I saw 3 3 gen diesel's on the way to work this morning. The chunky black truck smells like the egr was deleted. The purple one is my daily.

 

 

[dripley]

Google a 2000 ram cummins crank shaft tone wheel. It is 2 pieces and attaches to the crank. I cant link it. Might give you a better idea of what your dealing with.

[gsr46r]

Yes! found a couple here

https://www.ebay.com/itm/99-Cummins-diesel-engine-crankshaft-TIMING-TONE-RING-Trigger-Dodge-Ram-3942441/362783743812?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D1%26asc%3D20131003132420%26meid%3Da65c2588a79648689b63db1f08668c7c%26pid%3D100005%26rk%3D1%26rkt%3D12%26mehot%3Dlo%26sd%3D202642985027%26itm%3D362783743812%26pmt%3D1%26noa%3D0%26pg%3D2047675&_trksid=p2047675.c100005.m1851#viTabs_0

 

https://www.ebay.com/itm/Crankshaft-Tone-Ring-for-1998-2000-Dodge-Ram-Cummins-Turbo-Diesel-24-Valve/202642985027?epid=27031259456&hash=item2f2e769043:g:PjwAAOSwtNlco2fe