Another no start

[mudpie]

I'll start this thread the way I start all my threads. I'm not a Chevy guy...just a guy who happens to own a Chevy. Assume I know nothing about nothing.

I've got a '96 C2500HD, all stock except for an updated spider assembly. My experience with this truck is that it runs great, or doesn't run at all.

So it was running fine, driven daily to work, then I got a car and the truck sat for a couple months. Went to move it and it won't start.

I'm on my 3rd fuel pump in 4 years, so I checked fuel pressure. Zero. Put a jumper wire across the relay terminals 87 and 30 and got 60 psi. So I need a relay, but still no start.

Tested the ignition module at 2 auto parts stores. Tested good.

It doesn't seem to be sparking strong. Cap and rotor have a couple thousand miles on them and look clean, but the plug wires are kinda old so I put new wires in. Still won't start.

And now I've reached the end of my Chevy knowledge. What should I be looking at next?

Thanks for any suggestions

 

[mudpie]

I'm reading an article on testing the crank position sensor and it says that if the sensor is bad the PCM will not pulse the injectors to fire.

My plugs are fuel soaked, so I assume I can eliminate the crank sensor as a possibility, right?

Also read an article on testing the can sensor, and it Indicated that a bad can sensor will cause it to run poorly but will not prevent the vehicle from running.

Thought about a MAF sensor, but I replaced that a couple years ago and remember that it ran poorly but still ran.

I'm stumped

 

[mudpie]

It drives me crazy when I find a thread where somebody is having the same problem I am, and the thread just dies with no resolution to the problem. So, for anybody searching in the future, I think I got it figured out. Still have a couple questions down at the end though.

Long story, hopefully shortened...

The truck overheated back in September, and I found that the radiator was clogged. It sat for a month until I put a radiator in it, then I found the water pump leaking. I didn't need the truck, so it sat. In mid-December I tried to move it and it wouldn't start. The plugs were fuel soaked and it didn't seem to be firing, so I checked the ignition module. Two auto parts stores said it was good. My plug wires were old, so I replaced them. Still didn't run, but I didn't need it so it sat.

Now (January) I actually need the truck. I put a water pump in it, and started over with trying to make it run. Took the ignition module again to two different auto parts stores, and now it tested bad both times. Bought a new one...truck still didn't run.

I thought maybe I'd blown a head gasket when it overheated, so I checked compression. All 8 cylinders are somewhere between 195 and 205, so I'm good there. I put a timing light on the coil wire, taped the trigger back, and cranked the truck. The light flashed like a strobe light. When I attached it to the individual plug wires, the light didn't flash at all. I found my cap / rotor damp and corroded.

About 3 years ago I replaced a bad distributor. The replacement came with a cap and rotor. About a year later they were both corroded, so I assumed they were just cheap parts and replaced them with a lifetime warranty cap / rotor from Autozone. I hadn't thought to check the cap / rotor now because I knew that they were only a year old, and had maybe 5k miles on them.

So I got another new cap / rotor, and decided to read the instructions to see if maybe I wasn't sealing it properly or something. Apparently this is a common problem, because the instructions say (in bold letters) that corrosion in the cap is usually the result of a plugged vent in the distributor housing.

So now I'm thinking that's my problem, which is probably why the original cap / rotor went bad. I have to check, but I'm thinking maybe this aftermarket distributor I got doesn't have a vent at all.

So, questions...

Where is this vent supposed to be? I'm used to dealing with foreign cars that usually have a vent in the cap.

If I don't find a vent, is it just a simple matter of drilling a small hole in the distributor housing? I've seen threads where somebody drilled a hole in the cap and attached a vacuum line. Is there a preferred method to solving this problem?

Any thoughts appreciated.