Crank no start with pcm/idm faults

dieseldoc · January 10, 2017

I am working on a 2000 F-350 7.3 truck with an automatic trans. Customer states it has been intermittently buck/jerking and stalling for several months. Had the trans repaired for other issues. Customer was driving and states the vehicle will just all of a sudden lose power( feels like all of a sudden a heavy trailer was hooked up) than has no throttle response and sometimes comes out of it other times it will stall. He pulls over and cranks it will start right up sometimes not but after it sits a few minutes it will start and go just fine. He assures me there is no chip or programmers in the truck. Last week he was driving down the road and it acted up as mentioned above, he pulled over and restarted it and went 200 feet and it did it again and now is a crank no start.

The customer has tried to work on it himself and pulled the pcm out to test for power and ground and has finally given up and hauled it into me this afternoon. I verified powers and grounds to the pcm, ok. disconnected the batteries and installed the pcm and hooked things back up. Hooked up scan tool and powered things up, had lots of faults in memory, I assume from him having the key on with no pcm installed. I cleared all the faults and than went to pid data and checked for rpm and icp/ipr values. I had no cranking speed, he just installed an aftermarket cam sensor. I put a ford sensor in and tested, now have engine rpm. Icp/ipr behave correctly during cranking. cranking speed is good as well. I checked for codes after cranking a total of 30 seconds to verify icp/ipr and engine speed. I had in memory a P0605 and P1668 PCM-IDM communication error and P0470. cleared all faults, disconnected the batteries and turned the headlights on for 10 min, than shut the lights off and hooked up the batteries. Keyed on and ran a KOEO test it produced P0605, P1668, and P0470. I than cranked the engine for 10 seconds and checked codes and a P1670 is now present.

That is where I currently am at and heading home for the day. In the morning I plan to verify power and ground to the IDM and PCM again to make damn sure I didn't miss anything there. If that looks good that I plan to try my test PCM and see what happens than. Just curious from your guys experience is there something I am missing or should check first before trying a test module in? I personally have not had to replace a PCM in one of these trucks before, plenty of IDMs but never a PCM. So considering the price of the module and the fact they are a low failure rate item I want to make sure it is an issue before quote one. thanks for your insights and thoughts

Bruce Amacker · January 10, 2017

Did you check fuel pressure? Your first paragraph is a perfect description of clogged screens in the tank sender.

:grin:

Edit: Update your page so we know where you are- are you in the salt belt? Rotted connectors do screwy things.

dieseldoc · January 10, 2017

I have not checked fuel pressure and that yet I only had n hour today to look at it. I will have 2 hours tomorrow to look at it before my appointment for the day shows up. I am in southeast North Dakota. We have salt n corrosion but nothing like you guys on the east coast. Connectors I have looked at are clean n dry so far. Will put more details up or what I find is the fix as it becomes available.

dieseldoc · January 11, 2017

I started today with the no start diagnostic sheet on this truck and everything was checking out. I ran a buzz test this am and no buzz just the fault for ecm-idm communication fault. Ran through the pinpoint test for the code and all checked out. I plugged my test idm in. Cleared all fault ran the koeo test and got the p0605 and the ebp circuit fault. Ran buzz test and it passed. Cranked the truck and it started right up and ran with no issue. Plugged the old idm back in and crank no start n all posted faults are back. Ordered n idm will be here tomorrow. And for anybody interested the ford idm is actually $22 cheaper than the alliant power aftermarket.