Just food for thought... my 3.0 ran rough, went to check timing and it was off a lot, if I set timing where it should be it got worse so I just set it where it ran the best. Later on I had to change the water pump...I decided to change the timing belt as well and to my surprise I found a sheared key on my harmonic balancer...I had a lot of your symptoms and was puzzled as can be. I would never had thought about the balancer. Like I said "Just food for thought", This is the first I've seen or heard of. Good luck.

 

I know exactly what is wrong with your 3vze... it's still in your rig! I have the same problem, but soon to be corrected with the 3.4 hahaha

hoping the HG blow soon so I have an excuse to drop a few grand on a swap...

 

I have the same problem i think, my timings set at 30 degrees which made no sense to me before, i never thought of the key being sheared. When i changed my plug wires a year ago i checked the timing and set it back 12 and it ran about the same as you described in your first post, so i just advanced it to roughly were it was set before and then a little extra and been running it like that since. Def looked like like your timing marks were off tho but if that doesnt completely fix it id try messing with the ignition timing.

 

>> BINGO!! << Drove it today; It's a different beast!! It pulled with normal power right after a cold start. It idles smoothly, It sounds much less raspy a higher rpms. Big difference. I'm sure other things need to be taken care of, but this really helped.

I'm happy about this too because I feel like I'm getting to know the 3vze better, which is important because I own two 3vze powered Toyota 4x4s. After working with 22REs for years the 3vze looked a little daunting. I hope to graduate to the 5vzfe someday when I swap one into my 4runner so I'm counting this as good experience going forward.

Picture below: Marks now correctly aligned.

 

Well, there you go. I could've told you that all along. <<<ducks beer cans, wrenches, and other heavy flying objects>>>>

 

Those high school peeps did not do a proper job on that timing job. And obvisously had no instructor supervision either. That timing was bad wrong and would cause all your issues. The Low compression readings would be wrong the valves being just maybe a thousand of an inch or 2 off the seat. I've seen the same thing to many times cause people are too lazy to set it properly and just like to "get it running and gone." The first post i read i had a feeling in was the timing belt off. Seen many 3VZ-E's get fixed and tip top after timing belt replacement "done right." Reset your Computer and drive it it will prob be fine now. Over time i have seen a few 3.0s have jumped 1 or 2 teeth on one side just from stretch and they will still run ok but not "tip top." Good job on find