VTX1800N1

I disconnected one injector at a time for every cylinder and the knocking noise never changed, indicating that the sound is not coming from the bottom end. Couple that with the noise being loudest half way down the timing cover on Bank 1 via stethoscope and my finding of the top bolt retaining the timing chain guide missing on Bank 1, I am fairly confident that the engine doesn't have a spun bearing. The short block was bored, honed, and rebuilt with forged pistons and rods.

The entire Bank 2 being low on compression does concern me. I would think that if cam timing were off, all cylinders would be consistently low, rather than the large spread in compression pressures I am seeing. That leads me to believe that it may be a valve sealing problem. The O2 sensor on Bank 2 is stuck rich, which is consistent with low compression pressure and resulting incomplete burn. Unfortunately, I did not assemble this engine. I find it unlikely, though, that if mistakes were made that they would all be on one bank, rather than spread through the engine. I'm still hoping for the best (slight cam timing error). It could also be a problem with the lash adjusters- either not pumping up or stuck. I've ordered a set of new ones and will install them while fixing the timing chain guide. I'll tear into it next week.

jwog666

yes i did mean lash adjusters, i have seen the cams be off 5 teeth and not have interference issues, for the piston to contact the valves due to the cam being off would require the cam to be off a quarter turn or so and then it would not start or run, check for oil at the heads, and check for correct cam timing. if either doesnt check out you have found your problem. you still could have more wrong but u wont know till you fix what u find

MaxxRPM

What ever your next move, I wouldn't make any rash decisions or purchases until you check the timing...........(I actually experienced this).

You can still have compression with the timing off (I did).
PTV contact is no guarantee your motor is shot (mine wasn't, in fact it runs just fine. These motors are pretty tough).
........And another thing.......DON'T drive it like this. If some of that noise is PTV contact, the last thing you want to do is put the motor under load.

oxfordgt

If bank 2 sensor 1 is reading rich you may have washed the cylinders giving you the low compression. Does the exhaust smell excessively rich? You need to find what's causing that sensor to read rich. Since it's only one side start with the intake and exhaust gaskets.

VTX1800N1

The sensor could have always been bad. The Bank 1 sensor doesn't oscillate near as much as it should. There were 148K miles on the car at the time of rebuild, and for all I know these could be the original sensors. New Motorcraft sensors are only $35 at Rock Auto, so those are on the way as well. I remember the seller saying that there was a problem with the O2 sensors. The fuel injectors were professionally disassembled, cleaned, and flow tested. The exhaust does not smell overly rich. You get the cold start ethanol smell just like every other engine, but otherwise it's not abnormal at all. The oil does not smell like fuel. There are about 500 miles on the engine since the rebuild.

VTX1800N1

Since there is no way to know how many miles were on the used cylinder heads, I think it prudent to replace all the lash adjusters and cam followers. Of course, I would have insisted on a complete head rebuild, but I wasn't involved at that stage. In order to do a valve job now, the engine would have to come out because head studs were installed.

MaxxRPM

I wouldn't order **** yet.

.........I know it's a lot of wrench time but I'd tear it down and set the timing myself and see what happens.
You realize by the time you buy new cam followers and lash adjusters, you could have just bought brand new heads.....right?

VTX1800N1

Um, no you can't. I got brand new followers and lash adjusters (Summit Racing and Rock Auto) for less than $365 total for the entire engine. Late Model Restoration, American Muscle, Summit Racing, and Butler McMaster all show the 4.6 2V PI heads to be discontinued by Ford and they have none left. Even when they had them, they were $420 - $465 per head, and I think those did not include the lash adjusters and cam followers anyway.

MaxxRPM

They discontinued them? That sucks.
Yeah, the ford racing heads use to come complete. All you had to do is put on the cam gears and go.

VTX1800N1

There only strange part about diagnosing the knocking noise is that it didn't get any louder when I took the oil fill cap off. Being that it's right above the chain guide that was flapping around and causing the noise, I would have thought it would change noticeably when I took that cap off. The cam phasers diesel noise in my 05 F150 was the same way, though.