New Build: Not A Happy Motor!

[ekopel]

So here is the background:
02 1MZFE Block with 97 Non-VVTi Heads (P&P ). Oil Passages blocked and all that.

The sensors and whatnot were from an engine that had a seriously spun bearing, so there is a possibility that it blew a knock sensor or any other sensor for that matter (that could have been due to serious knocking and vibration).

Car starts and runs, but there are problems.

Symptoms:
1) No power under acceleration
2) Serious backfire. Almost sounds like it is happening on the intake side vs the exhaust side.

Possible Causes I came up with:
1) T-Belt off causing the timing to open the valves during combustion
2) Knock sensors blown
3) Fuel leak (dont know how it would correlate, but it is something i need to fx)
4) Egr gases igniting in intake (highly unlikely, but if improper A/F ratio due to a bad sensor, can it be possible?)
5) Ignition timing off (highly unlikely, but definately possible)

What I am asking is what do you think is the probable cause for the backfiring and loss of power? I am assuming that the symptoms are correlated - makes sense.

[Luckynumber5]

It should throw a CEL for a knock sensor, cars are very picky about them. Same thing with the EGR. Bad ignition timing would also throw a cylinder misfire code or a random misfire code.

Sounds like the timing belt.

[Eye8Pussies]

sounds like the timing is off to me as well- easy fix

[ekopel]

super tight engine bay....
at least i wont have to pull the motor.
can you check the T-belt without pulling the crank pulley?
i know you have to pull the top part of the t-belt cover, but do i have to pull the bottom?

[Eye8Pussies]

yeah...I've done 3 timing belt changes on the 1mz...it's no joke, but compared to pulling the motor out, it's not that hard.

and if I remember correctly, you have to pull off part of the bottom cover just to fully remove the top cover....but I don't quite remember the exact steps.

[Novice_cardude]

Timing belt changes on the v6 are not that hard. Shop environment I can knock one out in about 2 hours ... and i'm the slow guy. With a floor jack and hand tools maximum should be about 5-6 hours. To check the timing, just pull off the top timing cover. It's easy to get off, a little bit harder to get back on. It goes behind a metal bracket that is part of the motor mount assembly, so takes a little finesse to get the top cover back on. Just pull the cover, line up the crank pulley, and get a mirror and flashlight to check the timing marks on the rear cam gear.

Has the motor ever run properly with this build?

And knock sensors if they're not working properly will mess with engine timing. If they sense a knock they retard the timing. The only codes that usually show up on a scan are for knock sensor circuit malfunctions. Most of the time due to rats. :P

[chronoti]

check timming and then for codes.

[ekopel]

ok so quick question. There are marks on the rear timing cover as well as the cam gears. I aligned the Crank pulley with the 0 on the lower t-belt cover, and aligned the two cam gears up with their corresponding marks on the rear timing cover. (the white marks) I ran the engine and the exact same problems were happening. I am reading through my manual and it says that it needs to be aligned by holes in the actual gear. which is it? I read through the manual again and its just not clear.

Im pretty sure the t-belt is done correctly. still no engine codes. Can't drive it because of the lack of power...

Also, I did not check the valve clearances. I'm now starting to think that that is the problem. Anyone think that this is the problem? Timing belt seems to be good...