Help! Truck won't start

[Jaxtech]

I have a 94 GMC Sierra..Pretty good shape. This is the 1'st time this has happened. Truck ran fine going to work and coming home (50mi total) parked her like every otherday. Next morning went to start her and she turns over but does'nt start. Now the troubleshooting begins. I checked the fuel pump relay and fuel pump. (ignition switch on and fuel filter removed) Replaced the fuel filter. No Change. Next Checked the ignition coil (after market MSD Performance coil) I jumped a 20g wire against the engine block and it fired like a champ. Next I replaced the cap and rotor (although it ran smooth the day before) No Change. Next and last I replaced the ignition control module and still no change. I poured gas directly into the throttle-body carb and tried to start her and she does'nt even sputter!!!!. If anyone has seen this kind of problem before and can point me in the right direction (am afraid it could be a timing belt but I don't know how it could happen while parked) I would greatly appreciate it.

[Silverado Brethern]

I had the same type of problem with my 97 and i replaced all the plugs and wires and it worked fine. Not saying it is a sure fix but might be good to try especially if the plugs and wires are less than new.

[ridered]

I agree try new wires if you put gas in the TB and got nothing I think you are not getting any spark

[Jaxtech]

Thank you for the reponses. I put a 20guage wire into the number 2 spark plug boot and watched it shoot clear blue spark to the exhaust manifold. I replaced the ignition control module cause someone told me they could fire intermittantly...no change. I spoke to some co-workers and it was mentioned that a computer sensor could be the problem. Next question is wich sensor can cause the engine to crank - have fuel - have spark and still not even sputter?....btw I checked the fuel injector inlet filters and they were clear. Any ideas would be greatly appreciated.

[Kevcules]

That's really strange. This problem sounds alot deeper than plugs and wires. Did you check more than one cylinder for fire? You say you poured fuel down the throat and not a sputter? You could try resetting your computer for the truck. Take off battery power and disconnect the computer,(mine is behind the glove compartment) then reconnect it after ten seconds. Really weird though. I have a 91 GMC half ton and works well (knock on wood). I am interested to find out what is wrong with yours. IT does sound like a sensor not picking up or could be a defective computer . Anyway, good luck!
Kevcules

[Jaxtech]

I'm giving up and going to have her towed to a mechanics shop. Before I do though I will try the reset like you said. Thank you everyone for the help and I'll be sure to let ya'all know what the problem is.

[Jaxtech]

Ok this one is a lil tricky...but seems to be common. I had a MSD ignition coil that had an leak in it. Now when ya run a jumper wire from the top of the coil ya get spark and at the spartk plug wires there was intermittant spark...I thought the wire I shoved in the spark plug cable was loose....but that's what clued in the mechanic to test the ignition coil. There was no "burn trail" on the ignition coil but when ya remove it and flip it over you could see epoxy leakage between the coil and heatsink. Anyway the mechanic explained it to me that spark takes the path of least risistance and it's easier to go to the block then pass thru spark plug. I replaced the ignition coil for $16 at Adavanced auto and I'm back on the road again. Thanx again for everyone' help.