I think I'v finally narrowed down my "engine noise". Iv thought I had issues with either my tappets or injectors, but with only 2500 miles since half my engine was replaced, and most of the rest rebuilt, I had a hard time accepting that. I'v read that the 3.3/3.8 engine's can have flexplate issues from the bolts being too loose. This causes an irregular ping/knock that seems independent of temperature (ambient or engine), gas octane, and oil level. If my noise was pinging, 93 octane would solve it. If my tappets were noisy, proper oil level or a higher viscosity should solve it. Nothing worked for me.

Now, my question is do our transmissions have an inspection cover? I won't have time to deal with the dealer for a few weeks, and would like to narrow down the issue myself so I don't waste their time, or mine. If it is the flex plate, shouldn't I be able to tighten the screws myself?

Thanks!

 

Are you talking about the 8 bolts that attach the flex plate to the crank shaft, or the 4 bolts that attach the flex plate to the torque converter?

If it's the 4 bolts that attach the flex plate to the torque converter, those are accessible by removing the torque converter access structural collar.
(This is from the FSM. I've never actually done it.)

 

I'm not sure which ones come loose, but I assume it's the 24 ft/lb bolts attaching the flex plate and torque converter if that is the problem. So the structural collar is removable? I checked my FSM and couldn't find any info on it.

 

Look in transmission removal. There is no picture, though.

The parts manual has a good picture.

I don't know haw to post a picture from a pdf page.

Edit:

In the FSM, under engine removal, there is a good picture of the structural collar.

 

I can tell you that I had an old Chevrolet that had a cracked flex plate and it sounded just like a rod knocking. Your flex plate may be cracked and not just loose. My Chevrolet was cracked all the way around where the flex plate bolted to the crankshaft. If that is your problem, you'll have to remove the transmission to be able to see the cracks, and replace the flex plate.