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Discussion Starter · #1 ·
I am a old gear head to put it plainly. This 4.7 is baffling to me. 2nd owner and too good a deal to pass up.At 200,000 I tore it down to install a new timing set and heads, the bottom end was good and the overall care the previous owner was impeccable. Here is my problem. She starts but runs rich, will not idle and dies after a min or two. Check plugs and most are covered in black soot, but not wet. I keep getting codes P0351,P0353,P0355, P0356,P0358. And while DTC present it will not restart. If I clear the codes and wait a min it will restart and after wiggling the wires on the previous cylinders with codes I will get sometimes No codes and other times different codes all dealing with then same issue-Coil related. I have done all the checking of voltages and ohm reading but find nothing wrong with andy coil packs. I have even switched the coil packs around. resulting in the same condition. I have been using the right plugs and clean injectors. electrical wiring is now exposed looking form shorts or chafed wiring to no avail. I have cleaned all connectors and plugins. checked and cleaned TPS, IAC MAP etc, etc. Everything seems to be functioning. Just not functioning at the right time.
When I put the new heads on, I made sure to have the pin on the cams as close to 12:00 as they could be in a relaxed position. I lined all sprockets according to instructions. to line up dark links in the idler sprocket window and install cam gears on cams, took a little effort and moved cams ever so slightly and assure you they were aligned right. or to the instructions. I might add I was at TDC # 1 cylinder. However, I am left to believe I was not sure whether I was in intake vs exhaust stroke. Can someone clarify if I am right, wrong or indifferent? I now realize I am getting too old for this kind of activity but refuse to accept the obvious answer. And by joining this forum and writing this is my way of asking for help. I have to solve this, cause my mind will not let me rest til I do. Thank you in advance for any responses I get. I have been reading a lot of other information elsewhere and have to say this forum seems to me to be the best, with real information a man can believe in I apologize if I have made any mistakes, this is the first time I have ever posted anything.
 

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Unless there is something unique about the 4.7, the bottom of the engine does not know the difference between TDC intake vs. TDC exhaust.
That is why the gears are different sizes. the bottom goes around twice while the top goes around once.

Given all the codes are coil related, I'd look for damaged wiring and the like.
 

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Discussion Starter · #3 ·
Thank you valiant 67, that makes sense. for whatever reason the left bank, the plugs come out black and the right bank are cleaner. I have driven myself crazy with the wiring. upon inspection they wire seems very hard and almost brittle. and when I do the wiggle test, this sometimes does change codes up. I have even swapped coil packs from side to side and have even achieved a no code reading but will not start. . If I clear the codes and wait a min it will start ,but not run on its own . seems smooth at 1500 rpm but dip below that and its irratic and rough up and down and dies. I was trying to eliminate the possibility of a mistake on my part when I set the heads on the block and having to move the cams a little to line up the dowel pin so the timing sat at 12:00. Should I set back at tdc #1 and pull the valve covers to check time?
 
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