I just joined this forum to reply to this thread. Here's my story, in hoping it may help others, and also help me with my next issue. The second issue to be cross-posted in correct place - I will edit and reference new post when I get it up.
I have a 2013 F150 FX4 Supercrew 3.5L ecoboost. A few extras, but I've kept this truck mainly stock.
History:
-Purchased 3/13
-5/13 a semi blew a tire on the interstate, in retrospect, the tire would have been a better choice to hit than the exit sign I took out. Hood, grille, bumper, headlight, fender, etc (tune of $12k), no frame damage
-early '15, about 28k, started noticing 2-5 second rattle on start.
-mid '15, noticed slow acceleration, misfire at idle (rough)
-at 34k took into dealer, dealer replaced plugs, wires, coil from a TSB. could not replicate startup. indicated rattle was from vacuum pumps and/or turbo spool. which i knew was not the case.
-intermittently continued, 1 -2 times a week average.
-at 43k, a few weeks ago, it started happening almost every start.
-I did a week of research. Videos. Printed copies of TSB for existing timing chain issue. Scheduled with my dealer & dropped off everything. TSB handed to them, one in the front seat, and a copy taped to the under side of the hood.
-The next morning they called, said thats what it was, said it would be covered under warranty. Recommended I did not drive until corrected.
-a couple days turned into a couple more, 12 days later I had my truck back. Parts took forever to come in. I stopped by a few times, engine out, disassembled, cleaned, ready to go. Actual chain & cams took the longest.
-Replaced 4 VCT's, chain, water pump, cams, sprocket, idler pulley, belt, new oil, new coolant, flushed trans, gaskets, etc.
-I had purchased an Easy Care package which is refunded if not used at the time i bought the truck, which thankfully covered rental (only 5 days). The dealer picked up the other 7 days.
My advice for taking it in would be to present video/audio evidence (this seemed to stop the "oh we couldnt recreate it" issue) as well as knowledge of the issue and a copy of the TSB.
My problem now is that I have had the truck back a few days and there's a definite tick to the engine. I know, DFI, high pressure valves, some valve lash sound is normal. The problem is I'm not sure how normal. Or if theres any kind of stretch or "learn" period for the VCT's. Audio clip attached (it made me zip it to be able to attach it for some reason)
View attachment idle under hood.zip
On the plus side - no rattle on startup!