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I have a 1998 chevy silverado 4X4 5.7L 350. I accelerated a little to much last night and maybe hit 5 thousand rpm's. The then truck started running really bad and sounded like it had the biggest misfire ever. I then pulled over, put it in park, and shut it off. I went to start it again and it would not start. I have checked everything and i dont think it has blown up. There is no anitfreeze in the oil, and the motor still turns over im preety sure. It is not getting spark and i have checked the cap and rotor and both look good. What could it be? Any suggestions?
 

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You might have jumped the timing chain or even broke it. If your crankshaft is not turning neither will your distributor. Pull off the distributor cover and crank. If the rotor doesn't spin then its broke. I suspect a break because there is no spark May have to pull one valve cover off and see if the lifters move during cranking.

I do not know if your engine has a throttle position sensor. If that went bad there be no spark but you would get a trouble code.
 
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I already checked and the rotor spins when the truck is being cranked over.the only codes i got was for an o2 sensor which i have had for a long time, and a new code for the catalyst converter. Maybe a bad coil?
 

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the distributor could be bad these on your engine fail around 175K miles. also the coil and the ICM if original should also be replaced too old.

check for rotor wobble if it is then replace distributor. arcing causes the ICM to fail. replacing the ICM and coil is a paired replacement .

high revs would stress out the distributor could also effect timing if the chain jumped . so check timing also but you say no spark... if the chain did jump, it would spark, just not at the correct time.
cranking the engine and no spark make sure you pull the injector fuses so the plugs do not get fouled when doing the cranking /spark testing etc....
make sure there is oil in in it .
 

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The other question I would ask, is how did you test for spark?
 

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The other question I would ask, is how did you test for spark?
I pulled a spark plug wire, put a screw driver in there and put the other end of the screw driver about the length the gab of a spark plug gap would be up to a ground. I then cranked it over and i did not see any spark
 

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the distributor could be bad these on your engine fail around 175K miles. also the coil and the ICM if original should also be replaced too old.

check for rotor wobble if it is then replace distributor. arcing causes the ICM to fail. replacing the ICM and coil is a paired replacement .

high revs would stress out the distributor could also effect timing if the chain jumped . so check timing also but you say no spark... if the chain did jump, it would spark, just not at the correct time.
cranking the engine and no spark make sure you pull the injector fuses so the plugs do not get fouled when doing the cranking /spark testing etc....
make sure there is oil in in it .
The cap and rotor are new. But the cap was lose when i went to look at it. I pulled the cap and that and the rotor looked fine. The reason it was lose was because the front screw was stripped. So i just got a little bit bigger screw with more agressive teeth and it made it nice and tight. And when it broke down it was smoking from the back of the motor, kind of were the cap and rotor and all that ignition stuff is located
 

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I pulled a spark plug wire, put a screw driver in there and put the other end of the screw driver about the length the gab of a spark plug gap would be up to a ground. I then cranked it over and i did not see any spark
Ok, a backyard test, but maybe good enough.

So, do the same thing at the coil and that will eliminate the cap and rotor. The spark will be different, maybe a lot longer.

Smoking at the rear of the motor...........that sounds like more than just a rev to 5k.

If you think the smoke was in the area of the coil, that could be the problem
 

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Ok, a backyard test, but maybe good enough.

So, do the same thing at the coil and that will eliminate the cap and rotor. The spark will be different, maybe a lot longer.

Smoking at the rear of the motor...........that sounds like more than just a rev to 5k.

If you think the smoke was in the area of the coil, that could be the problem
It only smokes when i crank over
 

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Hmmm, ok, you need to follow that smoke, something has shorted and is overheating.
If you can't tell where it's coming from, use your hand, it should be warm, maybe hot.
 

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It only smokes when i crank over
Man: Doc, it hurts when I do this.
Doc: Then don't do that.

OK, that doesn't help.

Is the engine totally cold when you get the smoke? Or are you relating symptoms when you pulled over?

Ted
 

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Man: Doc, it hurts when I do this.
Doc: Then don't do that.

OK, that doesn't help.

Is the engine totally cold when you get the smoke? Or are you relating symptoms when you pulled over?

Ted
From when i pulled over and while the motor remained warm. Now that it is cold, its not smoking anymore. Atleast that i know of
 

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From when i pulled over and while the motor remained warm. Now that it is cold, its not smoking anymore. Atleast that i know of
You make that sound like you know where the smoke was coming from?
 

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Well, you said no spark, so don't waste your time on fuel.

A meter on Ohms, might test the coil. It will find an open, it will find a full short/ground; but, it won't find a high voltage arcing to ground, you need a growler (a thing, not a person, haha) for that.
 

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Ok, so i figure out why it wasnt starting. It was the icm, it was completely fried. But now when im driving and i give it a little, I think its when i down shifts, it will like stall and go back down to idle rpms. I know my transmission is fine because if it was slipping it would make the rpms skyrocket. Any ideas? Coil, fuel filter, fuel pump?
 

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Dirty throttle body is a cheap place to start.
 
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