bucking in drive and OD

[Me78569]

I would start with obd and try to see if any codes are there.    I dont remember your setup, but do you have the 02 ecm with auto flash or manual flash?

[mossyoak71]

ECM and PCM and the ECM is automatic.

Edited March 27, 2018 by mossyoak71
Add

[mossyoak71]

On 3/27/2018 at 11:33 AM, Me78569 said:

 

Ok, well I finally got an OBD2 port wired in, and pulled the codes.

P0341- camshaft position

P0380- heater grid which is deleted

P0382- heater grid which is deleted

So I did some searching and everything I found said something about the tach going on and out. The tach on the quadzilla app has always been spot on with the aftermarket tach that I had to put on in order to make the Ford computer happy. So my question is what and how do I need to go about figuring it out. 

[Me78569]

well I am willing to bet the bucking is related to the cam code.  Clear it go for a drive, does it come back?  

 

[mossyoak71]

I cleared the codes and drove it today, still acting up. So I checked the codes again and they came back. Of course the heater grid will always be there. So I called around and got a cam sensor, and installed it when I got home this afternoon. What a PITA to get to. So I took it for a drive after I reset the codes, and it drove great. Now I didn't drive the 30 miles like I do 1 way to work, so we will really see in the morning. It also seems to idle better and doesn't surge when I put it in gear, I thought that was a byproduct of doing the conversion. Hopefully, and I have all my fingers and toes crossed, that I can enjoy it now. Thanks all that replied.

Edited April 3, 2018 by mossyoak71
Spelling

[Dieselfuture]

Good to hear, hopefully that does it.

[mossyoak71]

Well it lasted all but 1 1/2 days. Now the bucking is back. Some where I saw a trouble shooting guide, so I guess I will try that step by step to find the issue. I wouldn't think that the new sensor went out that quick, but who knows.

[Mopar1973Man]

On 4/2/2018 at 7:56 PM, mossyoak71 said:

So I called around and got a cam sensor, and installed it when I got home this afternoon. What a PITA to get to.

 

48 minutes ago, mossyoak71 said:

Well it lasted all but 1 1/2 days. Now the bucking is back

 

I would ohm test the wires back to the ECM pin to pin. 

 

Also since we are dealing with AC waveforms with the tach signal I would suggest having the alternator tested for excessive AC noise as well. During the time its bucking you could pull over and unplug the field lead on the alternator and see if the bucking stops if so the alternator is to blame.

Edited April 5, 2018 by Mopar1973Man

[mossyoak71]

On 4/5/2018 at 8:41 AM, Mopar1973Man said:

 

 

I would ohm test the wires back to the ECM pin to pin.  

I will do this over the weekend.

 

Also since we are dealing with AC waveforms with the tach signal I would suggest having the alternator tested for excessive AC noise as well. During the time its bucking you could pull over and unplug the field lead on the alternator and see if the bucking stops if so the alternator is to blame.

So I took all the wires loose from the alternator and it did not correct it. I even watched the video of moparman testing his on YouTube. When I tested mine as soon as I put the leads on the battery it read 4.7 vac.then dropped to 0 within a couple of seconds. Could this be an issue, and if so, could it have taken out the new sensor? 

 

[Mopar1973Man]

Sensor is nothing but a coil wrapped around a magnet. As the tone wheel teeth pass by it creates a small AC voltage with a variable frequency which the ECM count the frequency of the sine wave and convert to as RPM gauge signal. 

 

Again here we are back to something possibly flooding the electrical system with more AC noise that is possibly fouling the tach signal. It still could be a simple wiring issue to the sensor.

 

This is another reason I like to typically pull the field and the alternator fuse as well. The absolutely kills the entire alternator circuit and there is ZERO connection to the alternator. 

[mossyoak71]

Ok, so today I pulled everything off the alternator, and it still did it. So I took the wiring harness off and tested the wires and they ohmed out at 0 pin to pin. So the next step I checked the voltage on the 5v pin and it was there. So I did some more research and my understanding is that when a closed portion of the cam gear passes over the sensor it closes the loop and let's the 5v through. Then when the air gap passes it goes back to an open circuit. So with this I took the original one and wired it up on my bench and supplied 5v to it. As I passed a metal object in front of it the circuit closed and allowed the voltage to pass through. Then when the object was pulled away sometimes it would go back to 0 and other times it would stay closed till I passed 3 or 4 times. So I checked the new one and it was doing the exact same thing. So I am at a loss, and the only other thing I know to do is to buy another sensor and bench test it to see what I come up with. It still throws the CPS code. 

[Mopar1973Man]

3 hours ago, mossyoak71 said:

So I am at a loss, and the only other thing I know to do is to buy another sensor and bench test it to see what I come up with. It still throws the CPS code. 

 

Question. Where did you buy the cam sensor at? 

[mossyoak71]

I purchased it at Napa. Think it was a BWD sensor. 

[mossyoak71]

Okay so yesterday afternoon I left off putting everything back together I was so frustrated so this morning driving it has really gotten bad but yesterday when I was driving it really didn't buck. but the code to keep coming back every time I reset it so I'm just wondering if the alternator has messed up this sensor and if so my only option is to buy another alternator and have it tested before I buy it and another sensor I'm willing to try anything right now

[Mopar1973Man]

Possible. All I can say is try again. Double check the alternator and be sure.

[mossyoak71]

Just now, Mopar1973Man said:

Possible. All I can say is try again. Double check the alternator and be sure.

So my theory is to buy a sensor and put it in. Unhook the alternator and drive it. If it is good, then I know it's the alternator. Now I just got off the phone with Leece-Neville alternators and I asked if they tested for ac noise, he said never heard of it. Now XDP carries this brand, so what brand would you recommend? Thanks for the help.

[Mopar1973Man]

I'm still running factory styled alternators just unhooked the grid heaters and the problem remains gone for the time. So this points to the fact that grid heaters cause the alternator diodes to fail which in turn is the AC noise. 

[mossyoak71]

Well I went and bought a new CPS and installed it. Took all wiring loose from the alternator and the charging cable loose from the battery. Went for a drive and it was still doing it. I really want to just drive it off a cliff at this point, and would if not for all the other work I have put into this conversion. Now looking at the schematics for the ECM, the only thing that is left in the circuit is the ECM. Now when the truck is cold, it will not do it. Once it is warmed up then that's when the issue starts. Sometimes worse than others. When I pull the codes, it only gives me the p0341. So I guess I'm going to try and get another ECM. All my grounds are good, I rechecked them and double checked them. 

[Mopar1973Man]

You might try sending the ECM to any of the ECM rebuliders we have listed and see if that works out for you.

 

[mossyoak71]

So I've been dealing with this all week and today I hook it up to my trailer that's normally hooked up to it every day and it's not doing it but if I unhook it and drive it without the trailer load on it and start bulking so I don't know what the deal is. But it's still there it's just not as prevalent

Edited April 13, 2018 by mossyoak71