79 C10/350 died...then came back to life.

[kopeck]

I wish things would just break so that I knew what I had to fix...

Anyway, driving along a 55mph the engine just died on me, I didn't notice and sputter, bucking or anything like that, it was just gone.  I pull over, turn the key and it starts an runs for a second and then that's it.  No amount of cranking will get it going.

The gauge said it had a half a tank but I threw 3 gallons in to see if it ran out of fuel.  The gauge did go up a tad, but still no joy.  The accelerator pump seems to be working when I pushed it manually, I also poured a bit a gas in from the top...nothing.

A friend stopped and he had a set of pliers and a a long Phillips bit, we pulled a plug wire, stuck the bit in the boot to see if spark would jump to ground, nothing.  So we're missing fire, or it seems that way anyway.

I get it towed home.

This morning I go out and move my work stuff over from the truck to the car, for the fun it I turn the key and it fires right up and seems to run fine.  I get it into the garage so I can stick the batter charger on it and that's where it stands.

Any ideas?  If it stayed dead I would have started checking things in the distributor but now it's alive again so who knows what's going on.  I'm thinking ignition control module but who knows at this point. 

K

[bd]

Remove and inspect the distributor cap, especially in the area of the carbon button.  Look for evidence of pitting and ashy discoloration.  Check the connection of the B+ primary wire to its terminal on the side of the cap and inspect the three-wire primary harness inside the cap.  If all appear okay, replace the pickup coil and module.

[Stewart G Griffin]

Check both battery cables for condition and tightness.

[Captain Swampy]

I agree with the other guys. Check your grounds and battery cables first. It's probably your ignition module. After that check the coil. Look at cap and rotor while it's off.

I carried a module and tools in the glove compartment when it was my daily driver. They don't go out often, but there is usually no notice, they just quit.

[blazer74]

Don't overlook the coil itself.

[Irish_Alley]

Remove and inspect the distributor cap, especially in the area of the carbon button.  Look for evidence of pitting and ashy discoloration.  Check the connection of the B+ primary wire to its terminal on the side of the cap and inspect the three-wire primary harness inside the cap.  If all appear okay, replace the pickup coil and module.

to go with what he said

http://forum.73-87chevytrucks.com/smforum/index.php?topic=29995.0

If parts test bad check out eBay for being hei distributors for sbc. You can find them for around $50 and it will be all new parts

[kopeck]

Thanks guys,

Kind what I had in mind, just a visual inspection and then go from there.  I have a new cap sitting on the shelf anyway, probably grab a new rotator  on the way home just in case.  If everything looks OK then I'll get the module.

Oh the the battery terminals were tight.  I went though the grounds a year ago or so, they should be fine.

K

[kopeck]

Hi Guys,

Using Irish_Alley's coil test it looks like the primary side of the coil is shot.  You put the meter on it and the numbers jump all over the place but then settle to 0.  The Secondary tests fine...not that it matters.

Before I tested the coil (somehow I missed the link) I installed a new cap and rotor I had on the shelf.  The truck would start, run for like 15-30 seconds then just shut off.  You could restart it right off but it would do the same thing.  I stuck my timing like on it and it just like the key was switched off.

Think I should replace the ignition module too or just go with the coil for now?

Thanks,

K

[bd]

If you think it's the coil, replace it and see what happens.  No need to replace parts that aren't bad.  You can easily change the ICM if the problem persists - it's the pickup coil that requires removal of the distributor.

[79 Royal Sierra]

I just went thru this on my 79 c15 with 350 engine as well. The dizzy had moisture in the cap and rotor, so I replaced them. A week later same issues, so I just went ahead and swapped a new Spectre dizzy from Oreillys along with tune up, wires and plugs. No issues since I did this. Good luck and keep us posted

[kopeck]

She runs!

Turns out it was the ignition module.  I did install a new coil as well since the old one wasn't testing right on one side.

I took the opportunity to throw on a new set of wires and the cap and rotor I had sitting on the shelf.  The wires I put on 16 years ago were awful, just way to long, some had over a foot of slack!  I had a few coiled up and zip tied...not sure if it was just a poorly made set or if I was given one for another application, none the less it's much better now!

So my old, pretty worn, leaky 350 has a nice fresh ignition system. 

Thanks for the pointers,

K

[79 Royal Sierra]

Glad to hear the good news bud. I just bought a 90 camaro v8 and having to drop the dang rear tank that is full of rust, and ruined a new fuel pump and sender.

[kopeck]

It's never easy...

The last two days I've driven the truck quite a bit.  3 times it's it had momentary misses, it sound like it's coughing back through the carb (I heard a pop from the dash area).  Each time it's been after the truck was fully warmed up, let sit for a short while (30 minutes or so) and then driven normally.  It doesn't last, but for a few seconds and once it's done, it's done it runs fine.  I drove it for 20 - 30 miles at all sorts of speeds and loads and it runs fine.  It seem to happen fairly soon after starting and under initial acceleration (ie pulling out onto a road and getting up to speed).

Kind of sounds like a lean issue but A) I haven't changed anything and B) why would it fix it's self and do it so quickly.

Maybe a faulty new ignition module?  It doesn't seem like the cap, rotor, coil or wires would do stuff like that...

K



 



 

[kopeck]

So my truck is still having periods of missing badly.

It seems to be as it's warming up.  At high idle/choke set it runs fine.  When I first take off but don't push it/put the engine under load it's OK too.  As soon as I load the engine it breaks up, sometime coughing back through the carb.

After things get warmed up it seems to run just fine.  Today was the coldest (low 30s) that I've run it since this problem poped up so it took a while to "fix" it's self.  It never did this until the ignition module died on me.  I guess it could be a lean issue but I didn't touch the carb, it seems like it has to be in the ignition.

Any ideas where to start?  It's intermittent, which is frustrating as all get out.

K

[gunrac]

make sure you don't have weak springs or sticky weights in dist