I did test the camshaft sensor earlier, but I figured why not again:

I do get a strong 5v (5.14 or so) and also a 0 ohm (well, its like 1.## or something in the connector

I opened up the sensor, rotated the engine with my breaker bar, and the pulse spins, meaning the oil drive gear spins it so its all good.

I will buy a camshaft position sensor if I can find out to try out (and return if alls well), but still only thing I am thinking is PCM, especially after I try out this new crankshaft position sensor (which I thought reads the rpm's, not the camshaft)

thanks for all advice

Crank Shaft Position sensor is the primary source for RPM data for the computer. BUT, Tach signal is usually done off Cam signal, because it is much more simple to time off of, at least historically... That said, I could be totally wrong.

You saw my justification as to why I though you should spend time on the cam position sensor. Again, my conclusions could be wrong...

You may have an intermittent signal in the wires leading to the PCM as well. If you have a pin out of the PCM connector it is fairly trivial to test for continuity between the PCM and CPS connector...

PCM's are expensive, but very reliable. I would exhaust all avenues (cam and crank sensors) before assuming a bad PCM;More so because it would be a problem with a sensor. Sensors are low voltage inputs to an analog to digital converter. Usually you have some sort of power electronic failure, like an injector/coil mosfet.

Good luck, This one is turning out to be a bear.

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Analog to digital conversion can be problematic.

Poor connections (loose fit or dirty/corroded contacts) can cause weird problems.

The analog voltages are low level and susceptible to resistance loss due to poor connections.

The tach signal is generated off the crank position sensor.

The PCM is probably the most relaible part in the system, very unlikey to fail.

The signals have to be read by the PCM. The sensor signals need to be checked at the PCM, if you don't have a scan tool to read the data stream.

If the cam drive is good:
90% of the time, the crank sensor is failed.

5% of the time, it's the cam sensor itself.

4% of the time, the wiring harness is broken, or it's rubbed through shorting the signal to the PCM, usually at the rear head bolt stud next to the valve cover, by the firewall.

1% of the time, it's the PCM

Hope this helps!

today morning (about 10 hours ago) i got a new crank position sensor. Worked on it for a good 2 hours, finally got it off and put new one on. Now I get spark but I guess my timing is off, as it just won't start.

Will check compression again but now i have fuel and spark for sure.

thanks guys

the recirculating valve that goes from the top (of valve cover) into the air intake/to throttlebody is gone and that is the cause of the flames and fires shooting out of the throttlebody when pressing on gas.
going to change it tomorrow (stores closed now) and hope for the best.

You will need to check the sync of the cam sensor.

There is a small hole through the oil pump/cam sensor drive body that will line up with a similar hole in the rotating part under the grey plastic sensor when the engine is set to TDC Cylinder #1.

Set the engine to TDC #1. Observe the holes in the cam sensor drive to see if they line up. If not, loosen the hold down clamp and rotate the body until you can insert a toothpick, drill bit or small allen wrench through both holes. This will get it close enough to run. The cam sensor sync should be checked with a scan tool to verify that it's right at 0 degrees (TDC), but it will run "OK" +/- 10 degrees without setting a code. They do idle a bit better at 0 degrees, though.

If the oil pump drive is starting to seize, you may notice that there are witness marks on the base where the hold down clamp was originally installed, and the seizing drive has spun the itself out of position, usually the marks are about 1/4" long and will show nice shiny aluminum against the dirty part of the base. If the drive has spun, replace it and carefully inspect the camshaft gear by looking through the hole in the block at the teeth.

Hopefully, this helps!

so I worked all bloody day on this,

took out timing chain (it was sort of loose, replaced it) and made sure the timing is right on. The compression of the first cylinder goes on right before it hits the timing mark on the dampener.

i removed the valve cover and checked the rockers and all, turned engine and when the valves open, the camshaft mark is 100% correct (used some thin allen key i had).

so, its still backfiring but the timing is perfect, and so is the camshaft position in relation to first cylinder.

i am afraid the last thing is the PCM?

The answer may be somewhere in the thread; however, I need to ask an obvious question....

If it is backfiring after all you have checked, what is the condition of the plugs and wires???

Backfiring is either excess gas or an accumulation of unburned gas...

Or, is it a backfire or mos-fire???

Have you done a leak down test to make sure your valves are sealing?

When you had the rocker cover off did you make sure that all the lifters were going equally?

I've seen a leaky intake valve cause mis firing. I've also seen flat lobes act as if it is mis firing.

Have any of your PCM codes returned?
PCM's are soo expensive and they usually don't fail. And when they do it is usually a high power driver...
The only bad PCM I've ever seen was in a caddillac seville, an injector driver just stopped working. Every other time I've seen someone replace the PCM it didn't fix anything, but it did cost a LOT.