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Sick as a dog

97chevy350

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97chevy350 Enthusiast

97chevy350

Posted
Posted

97 350, shakin a little last nite when I brought her home form work this morning a little worse and as I started backin out of the driveway, started shakin like crazy with light. P0300, Mult. Rand. Misfire. NO KIDDING! Anyway, I dont know whats goin on. Hopefully someone can help. I use injector cleaner and ISO-HEET so thats not it.

Thanks

jhm Senior Enthusiast

jhm

Posted
Posted
97 350, shakin a little last nite when I brought her home form work this morning a little worse and as I started backin out of the driveway, started shakin like crazy with light. P0300, Mult. Rand. Misfire. NO KIDDING! Anyway, I dont know whats goin on. Hopefully someone can help. I use injector cleaner and ISO-HEET so thats not it.

Thanks

 

 

 

How much dry gas? I know people that have put too much in and engine will shudder like crazy.

plainvanilla Enthusiast

plainvanilla

Posted
Posted
97 350, shakin a little last nite when I brought her home form work this morning a little worse and as I started backin out of the driveway, started shakin like crazy with light. P0300, Mult. Rand. Misfire. NO KIDDING! Anyway, I dont know whats goin on. Hopefully someone can help. I use injector cleaner and ISO-HEET so thats not it.

Thanks

 

 

 

 

Sounds like omni spark and or coil pack, I'm not sure how the 97 Vortec was set up for spark distribution.

 

Probly NOT bad gas.

Stocklook Enthusiast

Stocklook

Posted
Posted

Hope this helps, on some OBS trusks, the distributor cap will crack due to heat from eng, and alow condensation in the cap, this will cause the engine to miss severely, you will not be able to see the crack, unless you put a bright light behind it, and if this is it replace everything (Cap and everything under the cap) because the condensation could have caused some corrosion.

 

Hope this helps, may not be the problem, just checking, this happend to my 90 GMC could not figure it out even the dealer said DUH. I replaced it all and then this old timer told me to check it.

tarantula Enthusiast

tarantula

Posted
Posted

Another thing to consider checking is the fuel injector wire harness plug (the big black plug) on top of the intake just behind the throttle body. I actually had mine come loose once, and some of the injectors weren't getting a pulse. The SES came on, then started to flash (usually indicates a serious problem). A more serious injector related problem could be a fuel line going to one of the injectors (under the intake) may have cracked or come loose. Obviously check the easy stuff first though. ;)

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