Originally Posted by TravisJohnson
Our issue was in fact the passenger side manifold. Not only was ours warped, it also had a crack in it. Along with that two of the bolts ended up shearing off.
The noise I hear in your video sounds like ours use to on a cold start, and the same noise was also audible when I held the brake and slightly accelerated... in drive not neutral or park. To make the sound the engine had to be under a slight load.
To confirm the manifold was the problem I had my brother come over and cold start the engine for me one morning. The hood was up and the immediate smell of strong exhaust was the tell tale. To confirm the side I basically smelled the air in the wheel well... passenger side had a strong exhaust smell, the drivers side did not. I gave up looking for the leak, but found it none the less.
The repair was costly! Turns out the drivers side manifold is like a 3 or 3.5 hour allowance, but the passenger side manifold is 6.5 hours. Top that with a manifold kit costing $250.00 and the kill shot is about a $900.00 repair. I don't recommend having the manifold resurfaced if it is not cracked, mostly because it thins out areas and to me prolongs what will be eventually a replacement. A new manifold was included in the kit I purchased. Our extended warranty expired in Jan 2012... I thanked my dealership for the wrong diagnosis as it was prior to that I reported the issue with the cold start.
I did call Ford and asked if they had any assistance for this repair, which seems to be a common problem that Ford is completely ignoring. They don't, so I told the rep on the other end that this issue needs attention as it is farily common and the dealership originally diagnosed the issue as a fuel injector issue and that it would not hurt to drive it until the computer logged a code. At least on the 2005 F150 with the 5.4L Triton... Ford has extended the fuel injector warranty to 11 years or 120,000 miles.
Don't wait to long... the longer you wait to get it fixed the possibility of bolt shear increases. It also affects the power.
One additional note... when the dealership mechanic put the manifold in place he bent an O2 censor. In doing that my check engine light came on and ultimately they replaced it at no charge, but what a pain to have to take it back to get checked the same day I picked it up.
Have to say though... no more noise and cold starts are normal now. So an expensive, but happy ending. Hope all this helps.