Another problem solved, only to find another

As some of you who have helped me may remember, I soldered all the splices I could find on my S-10 and all codes went away. 13, 22, and 45. My truck ran beautifully for the first time in the 6+ months I've
had it. FOR TWO DAYS!
Get this now - On the third day, I was coming home from work, 40 mile round trip. All of a sudden, going up a hill the truck began to lose some power and I thought it slightly stuttered, only then to start rapidly and violently mis-firing and sputtering back fire through the throttle body! pop-thud-pop-thud-pop-thud-pop very fast against the air cleaner housing. Totally bizarre stuff. Of course I pulled over to the side as I tried to keep it running till I could get under the hood and pull off the air cleaner. I pushed the throttle open and horrible harsh clacking and flames inside the intake manifold. The damn motor sounded like it was going to fly apart. It died. I pulled the positive battery cable for 30 seconds, put it back on, started it up, and the misfiring was gone! WTF? For the next two days this truck would do this midway to work and midway back. Each time I disconnected the battery cable, put it back on and it was good as new. WTF? Tonight on the way home, I took a long route and it didn't miss once. WTF is going on with this crazy truck?
Hatt
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possession?
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Hatt,
Pull the distributor cap off, remove the Ignition Control Module and take it to Autozone to be tested. Backfiring thru the TB is caused by one thing, a timing problem. Because it runs fine after resetting the ECM, this tells us it's not a timing chain problem, the dizzy hasn't jumped a gear or the like, but it's a problem with the electronic ignition system, which consists of the ECM, the ICM, the inductive pick-up coil, the ignition coil and the ESC system if so equipped. Start with the ICM.
Doc
Doc

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and
I've
mile
lose
the
the
over
the
horrible
motor
up,
truck
new.
miss
take it

OK, I'll have to get in the gm manual to identify what this is tomorrow. I'm a little bit skiddish about messing with the distributor though.

Yeah. I thought maybe the computer was probably bonkers. That that could be the only thing that would tell the ignition when to fire, or misfire.

the like,

consists of

the ESC

Thanks Doc, I'll read about all those things tomorrow. I'm close to shit canning the truck and cutting my losses, but that would be really hard to swallow. Thats why I haven't done it already. Well, that and because I'm thick headed and don't know when to quit.
Hatt
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Doc is right on. Had this exact symptom with my 90. After 250K miles, the distributor and ICM were toast. Replaced the distributor, ignition coil, ICM and she spins like new. Carroll Senn Columbia, SC (remove NOSPAM to reply)
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ignition
pulling
you.
Hi Again Doc,
Well, I did decide to get the ICM, after thinking on it for a while, it looked easy enough to handle. Though I could have bought the entire distributor, with the ICM, pickup coil, hall effect switch and all for just a little more than 100$. This ICM by itself was almost 50$. I'll try to test the one thats on it before putting the new one in. This stuff is difficult to do when you only have one vehicle. Anyway, I got it cooling down with the hood up right now.
I forgot to mention one other thing that might be directly related to whats happening, and that is that the "check gauges," light comes on every time I brake to a stop. After sitting there for a minute, it goes out. None of the gauges shows anything abnormal, so I don't know why this is doing this. I'm wondering however if it might be someway electrically related to what else is going on. I also found out that I don't have to pull the positive battery cable to get everything back to snuff. Just sitting with the engine off at the side of the road for 2 or 3 minutes does the same thing. Something is getting hot. Wish I knew what.
Hatt
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250K
right?
about
while,
and
almost
in.
hood up

to
I'm
what
sitting
does
about
at home

to remove

tell
As I thought I said, or implied, that would require me to get someone to take me, or take a cab 15 miles. Anyway, I replaced it. The old one didn't have any of the silicone under it, thats supposed to keep it cool. Finished it, no "service engine soon," light came on, it ran flawless for about 8 miles. Then it started missing again. Soon as it gets to full operating temp I suppose. Only had a different rythm to its missing and popping is all. Then leaving it shut off for a few minutes didn't help, neither did clearing the computer, as it did before. I tried it at least three times. Drove it all the way home missing and popping like a big dog.
Hatt
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