no wires but ignition coil rail, new, plugs are new too.

What I am thinking is the timing of the spark sent by computer is wrong.

Also, when i attachd a compression gauge, cylinder 1 would get approx 25 psi when the alignment point on the damper was maybe 30 degrees off (not too much, but it was easily seen)

backfire or misfire? well, before we had fire coming out of the throttle body, now we just get a lot of gassy pops from the throttle body, but we did unhook a lot of things (sepentine belt is off, and all attachments)

like 2 weeks ago, it would start and die within 10-15 seconds, but then there was a loud bang and hasnt started since

He said he had checked the compression in the first 3 or 4 cylinders.. I'm wondering about them last 2 or 3 cylinders. He sure does write about a bad cylinder..
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

The computer is digital. It will be either working or it won't. When the chips wear out they stop working, they don't slow down. If the computer is getting a signal from the sensors, generating a fuel/ignition curve then actuating the mosfet/drivers, and the actuators are functioning makes me think that the computer is doing what it is supposed to.

I would re-do the compression test and also perform a leak down test if any numbers are even a little fuzzy.
What procedure do you use to do a compression test?

Poping from the throttle body means that there is burning going on in the intake. That means there is a source of ignition present in the intake. I can think of 2 things that would light off the fuel in the intake manifold.
1. Spark Plugs. (timing)
2. Burning fuel escaping past intake valve. (valve timing/burnt valve)

The timing is controlled by the computer. If you feel that you have verified 100% correct timing on the crankshaft position sensor and the cam shaft position sensor, AND they are working perfectly. Then, it could be something very screwy going on in the computer.

A burnt valve or flat cam lob can cause the symptoms you are describing. I would run a compression test and leak down test just to be 100% sure the valves are good. I would also watch the rocker arms when cranking to check for a flat cam lobe.

I am just so leery about changing out computers. Especially because you canÆt prove that it is broken except through process of elimination. I always like to find the problem and say look here is this part that is bad, I have done this test it failed, and by visual inspection you can verify it is bad. Process of elimination says look IÆve done EVERY possible think PERFECTLY and I know that this is the only other part that can be bad. There are a lot of subsystems to test to prove a computer is bad.
That said if you have the money to swap computers....

Did you check and set the cam sensor sync? The symptoms of misalignment match what you are describing.

i will redo a compression check, and will try and build or get a leak down tester (depends on how much it would cost to buy, making seems pretty simple).

i believe the timing is dead on, why?
new timing chain, gears are aligned, and when rotating you could tell when valves go down and up. at tdc the camshaft sensor pin is 100% right on, and a new crankshaft sensor is put in (with the spacer).

last time i did compression test on all of them, they were all 100, and seemed to stay at that time

when i rotate/turn manually, it reaches 25-30psi when i turn it first time...

You said you changed the coil, there is a difference between the 1999 coil and the 2000+ coil, they are wired differently internally, but look identical and the connector fits. Maybe the parts store sold you the wrong one. Retry your original coil, hopefully this may be it.

Normal compression is usually over 120, usually at 140 psi. The low result may be due to a weak battery, though.

alright! i will try that, sounds like something really unique (about the ignition coil)

the first time i done compression check (battery charger running at 250amps) i had 140 psi on first 4 cylinders and didnt bother checking the other 2, later on with just a battery, guess it was almost dead, was at 100 or so on all 6

Did You pull all the spark plugs before starting the compression check?
If the battery is that bad perhaps you should pull the battery out of something else and do the test with that newer battery.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

If you had 100 psi min. on all 6 cyl. you probably don't have a leaking valve. Especially if you had a low battery. MartyÆs solution sounds like it could be the best...

THANKYOU so much Marty and others!
it was the ignition coil! was the wrong year

THANKYOU! it started up like a charm right away!

woohoooo!