Doss300

Redid my timing belt, getting power to coil packs but no power to spark plug. Also showing code P0351, timing is dead on. It's turning over just fine and is getting fuel. Rewired all the coil packs and plug wires, brand new. I'm not getting spark to the plugs but I'm getting hot to the coil! Ran just fine when I pulled it in the garage, now won't start. Been at this for over a week!!! HELP PLEASE?!b04 Lexus GS300​​​​​​​

LeX2K

Need to check for a pulse at the coils. As you found out the coils are positive side always powered, negative switched.

Doss300

They're is a pulse checked that long time ago what s next

Doss300

There is now no RPM reading when turning over.

LeX2K

With the key in the ON position (not cranking) does the check engine light come on?

Doss300

Yes the lights on and showing code po351

TrueGS300

You damaged the crank sensor or the sprocket teeth while doing the timing job. The computer needs to see rpm to fire the coils.

kr777

Yep almost definitely the crank gear, its really easy to break when doing a timing belt job/crank seal and I spent heaps of time trying to find the issue. If you have a look at the gear they have very tiny teeth on them, even if one breaks it won’t run properly.

Doss300

No only damage if you wanna call it that is a little scratch from a flat head on the back side of the pulley where it don't matter all teeth are there and I have fire now re did the wiring and plug wire but still won't start turning over fast and running is dead on tried moving 180 and does exact same thing and have plenty of fuel cylinders are filling with it cause it won't start.... This is crazy what now have fuel have fire but no start come on guys help me out

LeX2K

You say the coils are getting a pulse, is there spark? What do you you mean by "re did the wiring"

Doss300

Opened up the main harness loom wires were cracked and green most way through stopped short of ECU by atleast a foot and wired the wires to the coil pack and yes we have spark

LeX2K

So you have proper spark and fuel, that only leaves lack of compression.

TrueGS300

I understand everything except where you say "tried 180*". If you moved any timing sprocket that far off and tried to crank, you would surely bend valves. Sounds like you are getting spark now, but I'm guessing its an odd cranking noise due to low compression. The "fast" cranking you are talking about is because the engine isn't compressing air anymore. Its free to just spin easy. The VVT engine is an interference motor and cannot be tried in different timing positions. Sounds like the head needs rebuilt and timing done correctly.

Doss300

You are correct it is an interference motor except it's bone stock and that gives just enough tolerance where the piston and valves won't touch also I made many rotations by hand before even thinking about turning motor over with starter and there feels like compression cycles and no stoppages when I did this every time I timed it and when I timed it over again I was only adjusting between the tolerance line and dot tdc and btdc