VEHICLE: 2007 Ford Explorer Sport Trac, 97k miles 4.6L
COMPLAINT: Engine light is on, runs fine and he said that he has already replaced the alternator recently. This is from a used car lot and as usual, he informed us that he is at his spending limit.
I went on a short test drive as normal to get a feel on a direction I think I should take. I didn't notice anything running wise, no noise or anything actually except for the MIL, so I connected my e-scan elite, several codes were stored, I took a picture of the info, then cleared codes. Next for me was a visual underhood inspection, overly obvious that somebody had been trying to fix the light, the cmp’s had been replaced, the wiring was redone in a rats nest fashion, from the cmp’s to the ecm, at least the original wiring was still intact, Just cut at the sensors and ecm, routed all around the engine bay.
At this point, I had Cigi call and get approval for me to repair the wiring and to replace coil for cylinder 6 for the P0356 coil F code, the coil was original so I felt it should be replaced.
He approved the work and after repairing the cmp original wiring, I verified the circuits with the ATS e-scope ttl out feature. I then started the vehicle, let it run awhile, no light!, I shut it off while removing all equipment, now test drive time! I start it up and the light came back on immediately, I connect e-scan elite and pull codes, P0345 is present, I clear and repeat the start sequence several times clearing the P0345 each time, occasionally P0349 would set as well, these are circuit codes in theory, I have done other vehicles that throw circuit codes when out of time but not vct Fords, so I check everything I can think of multiple times, cmp’s with ckp signals at the ecm, that didn't look correct to me, but I didn't have and couldn't find a known good waveform, so, I went in cylinder on both banks, ii didn't have two 3 valve hoses, so I ordered one to have later and borrowed one to test this with, the hoses were considerably different, but I can deal with that. The cylinder on the coding bank was definitely bad, the other bank was normal, it was the end of the day so I just ran the information through my head for the time being.
Before I could start again the next morning, the car lot owner came in checking on it. Now he tells us this was fine until it developed a vibration, he had that fixed, wasn't sure what was fixed, but was sure. I would see it if I looked under the vehicle, that is when the light came on and he changed the alternator, the part they changed for the vibration was the carrier bearing. He said the alternator didn't fix the light and he needs the light off but doesn't have much profit room so fix it cheap as possible.....is what it is there. By the time he leaves my matching hose arrives and I re run the in cylinder test with same type hoses, now both look and measure bad, since I'm not certain that will set the code and everything else check good, I sell him an ecm.
It took six weeks I think for the computer to come, bad call on my part, same situation on codes.
I had spoken with Dave Hobbs recently about us having an old guys day and he came down for the day.
I pulled the timing cover the night before he came and found the hyd tensioner on the coding bank wasn't applying any pressure and a broken guide on the other bank, I believe that this is why that bank in cylinder tested bad.
Now for my next bad decision, these chains have four colored links, two per chain for setting the components correctly, I can see three of the four clearly and the alignment marks on the sprockets, so I count the links to the marks, all three were the same and looked to physically be in the correct locations, back together with a new guide and hyd tensioner, only together enough to test.
Grrrrrr failed again, I look T cmp/ckp and in cylinder again, bank two looks out to me, apart with the timing cover again for a closer look, I should have used my ATS inspection camera the first time, bank two timing chain is one half of a link out at the crank, remove the chains and reinstall correctly, back together and re test.
If you are ever weary of the colored links, lay the chain flat and mark one link on each end. The 5.4 3v is one link on one end and between two on the other end, but the same process applies. 3v engines on Fords will trigger the circuit faults when out of time. Great process and documentation! 5.4 diag.net/file/f5412vvlq… 4.6 diag.net/file/f1odcnsvt…
"3v engines on Fords will trigger the circuit faults when out of time" - when you publish/sell your secret master list, Chris, lemme know :-)
Just experienced a bunch of these no master list. I'll have to start logging this stuff into a book one of these days.
Thanks!, I am aware of the link configurations, I just wasn't positive the repeating code would set from out of time, I ignored the P0340 and other codes since someone had been all into this thing, I opted to chase the returning code only. I now am fully aware that Ford will use this logic sometimes. When he picked the vehicle up, it became evident that he had someone inside the timing cover too…
Rusty, I have found that when a manufacturer says "circuit" it doesn't always mean "electrical" circuit. Especially with transmissions it could mean "Hydraulic" circuit. Possibly the same with engine hydraulic circuits. Just something to think about.
I wish we had a master list for that Bob. Sometimes if you read "set criteria" you can discern that if the signal doesn't align, the PCM calls it an "incorrect signal" and an incorrect signal "must be" a circuit fault. They were still learning along-the-way in 2007...which is considered new out here :-)
Yeah Bob, I knew some do have that strategy, I did not think 3V VCT Fords used it. Thanks! Sorry, somehow I responded on the incorrect person
Bob- Agreed. Same with MAF "circuit" codes. Many guys get burned not realizing the air pathway for the MAF is considered a "circuit"