Bruce Amacker Posted March 14, 2012 Share Posted March 14, 2012 Hey Guys: I’m helping a friend/student in FL right now with a tough one and would like your joint opinions. 2005 F350 4x4 130k 6.0 The complaint is an intermittent no-start, usually after a hot soak of about an hour. The problem has been going on for several years but gradually getting more frequent. At first it was every 8 months or so, now to the point it is weekly or better. At first it was towed in several times when the complaint happened where it would start right up after arriving at the shop. If left on fast idle at the shop it never builds enough heat to recreate the problem. Over the last several years the following have been replaced- ICP, IPR, and CMP for various reasons. The CMP pad was super clean, no rust jacking. Replacement of these parts did not affect the problem. The tech had the owner disconnect the ICP once during a no-start situation which did not change the problem. The tech also went out on a service call twice to have the truck start right up when he got there. The latest time (late last week) the truck would not start, sat overnight, and the batteries were stone dead the next morning, even though when the tech arrived he could find no accessories left on. It was towed in, batteries charged, (no slow drain measured), sat 3-4 days when I arrived. I checked the GPM connectrs to make sure no melting or other visual problems were evident and pulled a bunch of codes (dead battery) like CMP, CKP, 4x4, key switch, several U1900 from different modules, but no ICP codes. I wrote off the CMP/CKP from extended cranking and don’t really trust the others are relevant. On the IDS I graphed ICP, IPR, RPM, FICM MPWR, FICM Sync, Sync, and tried to start the truck. It started within 3 seconds of cranking but Sync flipped back and forth several times between Yes and No on the bar graph I selected, only on the first start, and only for the first 2 seconds of cranking. IPR was within limits but I didn’t warm it up fully to see if it came down to 23ish. Looking at the IPR/ICP relationship graphs, the first one showed just a bit of high IPR for the 3 seconds it took to light but subsequent start graphs showed IPR much lower, which I wrote off as bleeding the HP system on it’s first start in several days. PCM/FICM programs are both current and MPWR was fine, 47.5. Fuel pressure was checked last time and 50something. Maintenance has been spot on with this guys’s whole fleet with OE filters, and he has several 6.0 trucks. It runs and drives virtually perfect when it runs. Right now I’m thinking about pulling the VC and checking the dummy plug o-rings, but the intermittent nature of this makes me wonder if this is the case. I brought along a known good PCM from up north and might try that for S&G. I neglected to bring a GPM which I think could be the source of the troubles, U1900s, and dead batteries. I’m unsure of my diagnostic direction and looking for suggestions. I don’t recall seeing a HP leak be so intermittent like this, I’m concerned about the U1900s and possibility of a harness or comm problem, or a funky shorted GPM. I don’t remember seeing Sync flip back and forth like that on other trucks, and the engine was cranking at a good speed. Any comments or suggestions are welcome. Thanks! Quote Link to comment Share on other sites More sharing options...
mchan68 Posted March 14, 2012 Share Posted March 14, 2012 With FICM_SYNC and SYNC flickering like that, I would be inclined to believe you have a harness issue. What about ICP psi, ICP desired and IPR duty cycle? Have you ever seen it go to 870 psi and 33% IPR duty cycle at idle? And rolling the dice on a set of dummy plugs can't hurt anything, if it's the late '05 that uses the 10mm allen plugs (not the early '05 that use the 1/2" square drive plug that never fails). Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted March 14, 2012 Author Share Posted March 14, 2012 I never saw the ICP/IPR go to the defaults you mention. Build date is 12/04 so I don't know which plugs it has. Thanks! Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted March 14, 2012 Share Posted March 14, 2012 HP oil leaks like the dummy plug/stand pipe d-rings can start out as intermittent and random but the length of time that this concern represents exceeds what I would think is typical of that failure. Usually when they go bad they progress fairly quickly from my experience. None the less, without concrete diagnostic evidence pulling them out and looking at them can't hurt anything. I agree with Mike that it is electrical as the sync issue seems odd. I recall one truck in my shop years ago had a FICM intermittently not waking up... and at times not shutting down... killing the battery. Quote Link to comment Share on other sites More sharing options...
cbriggs Posted March 14, 2012 Share Posted March 14, 2012 Has this thing ever had an stc fitting kit done? I have seen a bad stc be this intermitant, for a long time before it finally failed. We all know how good the 05's were for these.... Kind of a big job to dive in there without actually documenting that it is caused by low icp. Quote Link to comment Share on other sites More sharing options...
DieselD Posted March 14, 2012 Share Posted March 14, 2012 I am leaning towards a engine harness issue with the type of concerns you are having with it. I have had one very pretty close to the same concerns. Very random no start issue and every time it would get towed in it would fire right up. After several attempts to duplicate and a couple road calls to the customers house to look at it I finally caught it long enough to verify the loss of sync due to a circuit issue on the cam sensor circuit. Replaced the engine harness and all was well Quote Link to comment Share on other sites More sharing options...
Fordracer Posted March 14, 2012 Share Posted March 14, 2012 This is a perfect situation for a VDR. I have one VDR left that I haven't sold yet and with all the help you give us I would happy to send it to you if you want to use it. It does sound like a harness issue. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted March 15, 2012 Author Share Posted March 15, 2012 Hey Guys: Found it- it’s the STC fitting! Here’s what I did today- I called my buddy and told him to drive the truck, run it in the lot at 2000rpm for two hours, then shut it off and let it hot soak for an hour, then I’d show up and use his IDS again. I graphed out the same PIDS as yesterday and it wouldn’t start with no ICP buildup. We pulled one VC and the dummy plug (Allen hex) to find it looked like new (!?). Doing an air check sealed the deal- there’s a big air leak in the back and the IPR works fine. He’s pulling the turbo now but I’m pretty confident it’s going to be the STC. Here’s some screen captures from today, note sometimes it started and sometimes not, and the funky Sync dropout that had me going down the wrong path (perhaps). Even when it did start, the IPR was waaaayyyy up there to light it off, not like yesterday when it was cold. The .62 mile CLRDIST was funky, too, he had driven it more than that today. I’ve seen this be wrong before, also- any comments? Thanks for the help, I appreciate it! Thanks to Fordracer for the VDR offer. That was my next step...... Quote Link to comment Share on other sites More sharing options...
DieselD Posted March 15, 2012 Share Posted March 15, 2012 sneaky bastard Quote Link to comment Share on other sites More sharing options...
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