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hey guys you have been having such great luck here fixing these sync problems i figured i should join the club. So i bought a 2006 f350 that just had a rebuilt engine installed, new cam, ext.. well the guy i bought the truck from installed the engine and could never get it running right it off of him hoping i could figure it out. haha we will see its been a pain so far

i am having similar problems you guys have been seeing i have no sync, but i do have ficm sync. the truck will start run like crap sounds like an injector knock, or the timing is off (I hope not) but is what im thinking.

i have rmp on the dash and on ids. have done the volt ohm and hz test on both sensors and everything was within specs, i even swapped out both cam and crank sensors for new motorcraft sensors.
while i had the crank sensor out i looked through the hole and checked all teeth on the tone ring and could really see a problem? maybe i should try moving it with a flat blade i think i saw it mentioned that it can come loose. also tried swapping the wires for the crank sensor haha figured it worked for someone else i would try it but no luck i didnt try that on the cam sensor though.
20200326_094714.jpg


i did get it to run a relative compression test it usually would fail but it finished one for me not sure if it tells me anything maybe someone will have an idea. i will try to attach the photo
also i pulled this pcm out and it ran just fine in my excursion so i think that should rule out the pcm.

let me know if you guys have any ideas i would be great full thanks maybe i need to pay someone to come put a oscilloscope on it? thanks in advance
 

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I would have someone put an oscilloscope on it. You can find out if the cam is off a tooth by counting the spikes and comparing it to my scope. Someone else had a cam sensor wired backwards so you could try that too.
 

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I do think im about to that point to try and find somebody to scope it. I did find something odd today when i tried back probing the crank sensor i noticed that ficm sync didnt stay synced but it spiked a few times see attatched photo but would not start while it was being back probed. But if i took the probes off ficm sync stays yes and truck starts i rarely see a spike on the sync. 20200323_131627.jpg
 

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i did do that same test on my excursion and it would stay running while being back pobed on the crank sensor. So not sure if that tells me anything im wondering if that circuit may be weak even though the tests i have done on it check out normal over 150 hz while cranking. The pig tail on the crank sensor does have a broken locking tab would that be a problem? I have a new pigtail on the way. and let me know if these rmp screen shots look wierd
 

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hey guys i have an update haven't done a scope yet because i found an issue, i decided to recheck everything and what i found was if i had the key on both sensors check out to the pcm i am reading them in hz the cam sensor is 1.2 to 1.4. But when i read the cam sensor leaving the pcm pin 20 the hz reading is now at 10 or 11 and is supposed to be that same 1.2 to 1.4 hz that is coming from the cam sensor. On a diagnosis page i found it says at this point to replace the pcm but i have ran this pcm in an excursion which to me says its not the problem. Maybe a ground problem to the pcm? i am not sure if anyone has an idea let me know
 

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I know jamiesaun on here is very knowledgeable. He did say in one of his posts to check the grounds to the pcm. Also is that reading with the ficm connected? Maybe try disconnecting ficm and check your reading. I thought I read somewhere when I was researching my issue that a faulty ficm could cause a cam crank no sync. If I have a chance I could take a reading on my truck. What pin are you checking? Are you checking with key on or off?
 

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middle connector on the pcm pin 31 and 43 i have the 1.4 hz reading while cranking key on. When i connect to pin 20 and 43 it jumps to 10-11 hz key on kranking.
I found this on 2006 f250 6.0 losing ficm sync
It had a good trouble shooting guide. I also tried the pin 20 to 43 on a 6.0 excursion and it showed the correct 1.4 hz. What would make my signal multiply by 10 any ideas alternator feedback? i dont know i might try removing wires from the alternator and rechecking.
 

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alternator made no difference disconnected, i also tried your idea of disconnecting the ficm connector from the pcm when i did that i would get a 0 hz reading the weird thing is i tried it on the excursion (runs with no problems) and it did have the 1.4 hz reading with the ficm disconnected kinda weird not sure what that tells me. One other thing i noticed is when connected to pin 20 and 43 i had a -2.9 dc v reading vs a -.0135v reading on the excursion. all these readings are back probed at the middle ficm connector
 

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I will try to check readings tomorrow and let you know what I find. I think you really need to scope it though to see what’s going on. That’s the only tool fast enough to actually see what’s happening.
 

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Well finally got a chance to take readings. The cranking hertz was hard to tell be cause it started pretty fast but it looked like around 1.2 hz cranking and then 6.2hz running. This was on cam sensor wires 31 and 43. I then checked pin 20 and 43 and they were pretty much the same readings. So I was re-reading your post, so the engine starts but runs poorly? Never has cam crank sync but gets ficm sync? I would really get it scoped to see where your at. You can check cam timing and cam and crank signals at the same time. If the engine was rebuilt it could be a real possibility the cam timing is off. Did you ever check to see if there is any rust on the block where the sensors go?
 

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hey thanks for looking into it. the block is really clean when they did the rebuild they cleaned it really nice, but i took a piece of sand paper and tried to see if i could make it any better that didn't make any difference. I have decided that i think the timing is off so i pulled to cab today and will check the timing tomorrow. I really think its going to be off a tooth i will let you know. If it is do i have to pull the heads just to turn the cam just 1 tooth? Im planning on pulling that crank adapter that your not supposed to pull off haha but we will see tomorrow what i find
 

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Well what I was planning to do if I had to reset the cam if it was off, was to pull the engine and put it on an engine stand, flip it over and pull the pan and bed plate, then lift the crank up just enough to line up the marks. Thought that would be less work than pulling the heads. I guess it’s a tossup!
 

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well good news and bad news
bad news is i didn't find the problem the timing is on. good news is that the timing is on haha crap i may just swap the engine harness at this point
 

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So I just watched a new video on powerstroke help.com this morning. They had a problem with no cam crank sync. Turns out the crank tooth wheel had a slight bend in it causing the problem. Someone had rebuilt the engine. So they swapped in another crank and it fixed the problem. So I would check your tooth wheel for straightness if you have it apart.
 

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Sorry for the troubles!! But thanks for posting a conclusion!
 

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I guess it’s real easy to bend the tone ring. where all the big holes are it’s not too sturdy. Even setting the crank down wrong or leaning it on the ring can bend it! And the area on the crank sensor that actually reads the ring is very narrow so it doesn’t have to be a big bend. Well I’m glad you found something! At least you didn’t do all that work for nothing! Keep us updated how you make out
 
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