PSA - 100 series timing belt (1 Viewer)

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I suspect that when it was earlier stated that there was 'no compression,' the compression actually wasn't tested. The mechanic just assumed that was the case because the belt had broken and it wasn't running with new belt, and he may not be familiar with the argument on non-interference vs. interference on the 2uz (can't blame him too much there, the books do say its interference).
Glad its running again though, and I'm not sure if I'd be too concerned about that variation in comp in 7 and 8. It was probably there before, s*** gets worn.
 
Glad it ended happily. I too had to go through compression checking an engine myself in a similar-ish scenario. Sadly in my case the motor was indeed toast. But the lesson is always verify it yourself.
 
The engine runs a little hotter towards the back end, and with lower compression on 7 & 8 being equal- maybe thats a good thing as lower compression would run a little cooler.
 
Mud saves someone thousands yet again.
I cant even imagine the amount of money mud has saved me over the past 15+ years. Thank you all again!!
 
Update
I received a video with the truck running. It sounds correct and good.

When the belt broke, it destroyed the crank position sensor. A new sensor was installed a few days ago and that is when there was zero compression on all cylinders. The new sensor from Toyota was actually bad. A new crank position sensor was put in today and it fired up and sounds ok on the video. Compression on bank 1 was 170-170-170-150 and on bank two 170-170-170-150.

I am hoping everything is ok.

Persistence and ih8mud family paid off.

Thank you for all the assistance!
Happy to hear you're back on the road again! :cheers:

But from beginning this thread has had confusing information on reports of compression or lack of. Possibly it's a matter of interpretation, form shop to how unstood and written here in mud.

But to see compression like this. First to have zero in all 8. Than on final reported, even 170PSI on 6 cylinders, which is a low number unless done cold. If cold seems high, but would explain no variation in readings. Then too have rear most cylinders drop to 150PSI, evenly from side to side, what are the odds!. I assume rear most, as the way written implies.

Done cold is not a good test, to determine health of engine cylinders or heads. As they are done with engine at operating temp.

Second a cam or crank sensor has nothing to do with compression. Compress is purely mechanical. You can disconnect the sensor and compression will not change!

Here's a reading hot, 4.7L w/<300K miles at 5K above sea level:
1-190, 3-192, 5-192, 7-197, 2-197, 4-195, 6-175, 8-191. Here we do see a weak cylinder #6.

When done cold, they look more like this at 229K miles:
1- 150, 3-155, 5-120, 7-150, 2-47, 4-150, 6-150, 8-155. #5 at 120PSI is weak. #2 at 47PSI is a bad cylinder, leak-down test suggest bad rings/cylinder wall.

If timing off on bk2 cam, they look like this:
Bk 1: ~150PSI
Bk 2: 2-10, 4-10, 6-35, 8-20PSI. Wet with fuel.
 
Second a cam or crank sensor has nothing to do with compression. Compress is purely mechanical. You can disconnect the sensor and compression will not change!
This.
It won't run with a bad crank sensor yet a bad crank pos. sensor has no impact or bearing on compression testing or internal mechanical condition.

This to say, we don't have the whole story from the mech but the outcome is great as expected so we don't really need one.
 

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