i had a rattle in top end of my 2008 Camry 4cyl.. assumed it was timing but didn't have time to take it apart . yes should have taken the time . as you can expect it took me out before i could check it out .
took it apart and timing guide was in pieces ,tensioner was apart. Replaced chain , gears , guides , and timed according to videos online . put all back together and tried to start but no compression at all .
assumed i messed up marks so did the job again. that sucked because all was lined up .still disassembled and reset again . checked for tdc and both lobs on cams facing out all marks set on tiny arrows.got it all back together and still no compression .at all any hints?

 

Any chance some engine head valves were bent?

 

i guess is possible i have not removed the head . this is a gas engine , everything i read said it is not a interference engine . am i incorrect?

 

Can only guess.

Was the VVTi gear assy set up correctly? It does rotate.

Since you spent some time at the job, my advice is to spend $20 for two day access to Toyota's technical site.below. You can download the service info for installing the gears, chain, tensioner. The service manual is very specific and detailed about things with great diagrams!

https://techinfo.toyota.com/techInfo....toyota.com%2F

 

not opposed to spending 20 dollars if it will solve my problem . i do have a chilton manual for this car . is this download better?
i will be all over it if so. all marks line up and cams seem to be perfect in synch. any chance a crankshaft position sensor could cause this issue.

 

Can only guess.

Is the valve cover still off?

If so suggest you get the crank/cam lined up a 0 degrees TDC on compression stroke for No 1 (always rotate the engine CW at the crank). Then check if the valves are closed plus check valve clearance. Then rotate crank to get the next cylinder in the firing order at TDC/compression (No 3) and check valves/clearance. Repeat for other two cylinders (No 4 and No 2).

The VVTi changes the intake cam timing but doubt its enough to cause zero compression otherwise this would defeat its purpose.

Make sure whatever crank or cam pulley keys are installed and not stripped.

Crank and camshaft sensors can cause starting issues including no start due to timing but not zero compression.

Make sure the VVTi controller on the head is connected.

Is it possible the engine has a bad head gasket?

As to Toyota info versus Clinton, see private message.

 

First thank you for your advice and info that was very helpful .
Now everything I have read said that a 2008 Toyota Camry 4 cylinder 2.4, 2az-fe engine
is not a interference engine. I pumped air into the cylinder and rotated the engine by hand .
and used stethoscope on exhaust. heard air and as valve closed air stopped . thought about quitting there
but muscled through same on intake side and this time air was slower when valves were closed but the
hiss was there, and same on all cylinders. Unwillingly removed the head and shined light under the head
and could see lots of light in around all valves. now the debate for me is .
Do i replace valves or head?

 

One issue is the competing costs of any repair. Repairing the head may cost more then buying a reworked used head that comes complete with camshafts.

If you have a valve spring removal tool, remove the valves you think are leaking. Inspect valve stems for straightness (not bent) and valve/head seating areas and valve guides for damage and cracks.

Use machinist marking bluing (Dyken or such) to mark valve seat contract area. Seat the valve to head and determine the extend of contact/non contact seating area.

If you are replacing valves then the valves and their seats will need to ground to match each other (valve job). Check the head gasket surface area for warping as this may need to be trued. You will need new valve stem seals. After installing the valve train will need to recheck valve clearance and adjust if needed via the correct shim thickness. All this adds up.

Get new head bolts as they stretch when installed.

Check your head for damage (mark the valves to their specific hole in the head).

A competent auto machine shop can evaluate the current head and provide costs of any repairs.

Rebuilt heads are available with an internet search and a decent machine shop will have sources. Rebuild heads are running around $400. A valve job, head resurfacing, pressure testing, checking for cracks may approach this dollar cost.