1995 Chevy Silverado 5.7l doesn't have spark
 

Hi, I'm purchasing a 1995 silverado 1500 5.7l ext cab from a friend and I'm having trouble getting the motor to fire up, so here is my story:

Someone who was with us incorrectly hooked up the battery charger to the car, while one person was trying to crank the motor over. Instantly the battery cable started to smoke and get hot so we turned it off and disconnected the battery. We went and bought a new battery, put it in, and the truck fired up and ran smooth and rich for about 4 minutes, then it died.
So we tried getting it to fire up with starting fluid...nothing.. put a new coil, new distributor, new ignition module, new plugs/wires/dist cap/ rotor..and still no spark at all from the plugs...does anyone know what this could be???

I assume you checked all fuses inside the cab and outside under the hood. When you turn the key on does the service engine light come on and then turn back off? I am wondering if the ECM was damaged from the battery charger.

I've checked all the fuse boxes already and everything looks good. Also I'm not getting a check engine light up on the dash, my only assumption is the ecm is fried or the ecs module is ruined

Did the truck have a service engine light before the charger mishap????

no, there was no engine light before the mishap. I talk to a technician at work and he is suspicious that the timing chain guides may have broken since they sat for a while, causing the oil pump not to turn the distributor/rotor...so what I need to do is check it without the cap on. The motor has a bout 74k original miles

I would pull the cluster to see if there is a bulb in the service engine slot. Plug a scan tool into it and see what comes up. Let us know what you find.

I pulled the cap off and the rotor still spins perefect. Today I will look for the check engine light and plug a scan tool in. Also, I never though of this before but I think it's possible the ignition switch (not tumbler) is failing.

check fuse link wires. They can blow not tell it sometimes .
Have to pull on them or check with a meter.

well, i truck fired up today after replacing the ignition switch attached to the ignition lock cylinder. The only problem is that the truck idles rough, I set the timing with the gun and it seems like it has a slight misfire in idle and it wants to cut out and die when put in gear. So tomorrow I'm going to make sure that the wires were put in the correct order on the cap (since a couple diff people have touched it and removed them) I'm sure this has to be the problem, it's my only logical explanation especially after setting the timing with the gun and having all new parts.

Turns out the plug wires WERE in the wrong spot and the truck runs smooth! The only problem I'm having now is the truck has Horrible acceleration. In idle truck runs great, but as soon as I take it out for a spin the truck has hesitation trying to accelerate and has a strange hissing sound that dies slowly when you let off the gas. I replaced both the tps and map sensors and it still runs the same. Also, I've checked the vacuum lines and there are no sings of leaks. any ideas guys? Thank You

When you set the timing did you unplug the electronic advance wire?

That would be the coolant temp sensor , located beside thermostat housing.
Clean those grounds in that are while your at it.

Have you checked your fuel pressure? How old is the air filter? And fuel filter?

Maybe the throttle body could be leaking causing the hissing? A vacum leak will cause bad hesitation on acceleration on the low end.

This is true :)

The hissing is starving for fuel , more air than fuel.

This is what I'm thinking it definitely sounds related to the TBI. Possibly an injector leaking? (bad o ring?) I haven't checked the fuel pressure but the air and fuel filter are brand new. I will also clean the temp sensor terminals.

Shamrock, I did not unplug the advance wire when i set the timing.

Also, I've noticed the RPM'S dropped at idle and sit at about 800 now

Shamrock knows those TBI set ups pretty good. I have heard them leak from the flaps or base, I cant remember.

The injectors have a sort of "spattery sound to them and almost like a constant clicking, like a diesel motor. Is this normal?

yes that is normal the click is the injector opening and closing and the other sound is the fuel spraying out......sound like they are working but I would run some cleaner through just because. never hurts to be safe and clean them

OK, that sounds good. I figured the spraying sound was normal, but the clicking i was unsure..given that I've never owned a vehicle with TBI before so this is all new to me haha. I got some BG44k from work to run in the tank. I drove it last night and it seems to just hesitate to get up to speed, but then again it hasn't been driven in a while so I need to drive it to help cycle that injector cleaner

Problem Solved. Thanks Everyone!

Come on buddy post up the solution. Maybe in the future someone else with the same problem could use this as reference.

well that's why i quoted shamrock. The problem was that the electronic advance was not disconnected when I originally did the timing...boy do I feel dumb haha. Once I disconnected it, loosened the distributor, got the timing light and reset the timing back to where i wanted it. After that I turned off the truck, reconnected the wire and fired it up..sure enough it runs beautiful now!

Ahh dont feel bad, I did the exact same thing with my 92 Iroc. Glad you got her fixed!

Thanks Everyone for all the help!:D

The hissing sound ... starving for fuel. Get the coolant temp sensor out of the ..equation.
Beside thermostat housing.. clean the grounds in that are also.

i have same problem
 

i replaced alternater ,coil,plug wires,dist cap , module,and computer. after everyone of those the truck would start i would run it 30 min. and then it would not restart the last one was the computer it started i drove it 5 miles.the tranny started slipping it never slipped b4 that time shut it off sunday and it will not start again and there is no spark again. im stummped cAN ANYBODY HELP!!!!! thanks its a silverado 4by4 1500 extended cab 1995