Random cylinder msifire!!!!!!

[Fast 95]

99 Vortec 350, new plugs, wires, cap & button, temp control sensor, 195 thermostat, and fuel filter. It keeps throwing a P0300 code, "random cylinder misfire". What else could cause this, and how di i fix it?

 

[///RAGMC]

Ive herd of a bad coil causing this before. How old is the coil?

 

[Fast 95]

Well truck has 174,000, motor has 92,000, so im not sure which one was used when the motor was changed. I bought it after the motor was swapped, the only thing i have changed is what i listed in the first post.

 

[Hodges87]

Have you checked your dist gear? I had the same problem but it happened at higher rpms. I checked the dist gear and it was worn, so I replaced it and it solved the problem. Also the poppet style injectors are known to cause multiple misfires.

 

[Fast 95]

I will now, thanks.

 

[Hodges87]

Make sure you have a scan tool available when you check it, because your timing has to be set back with a scan tool that reads "cam retard"

 

[Fast 95]

What if i just swap it out the whole distrubitor with a new one from Summit?
http://www.summitracing.com/parts/SUM-850098/

 

[Hodges87]

Here is the one I have http://cgi.ebay.com/ebaymotors/Chevy-GM-Ignition-Distributor-Vortec-350-V8-5-0L-5-7L_W0QQitemZ270493266891QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item3efaa7b3cb

 

[Fast 95]

Never thought to look on ebay, thanks. I dont have a problem buying a whole new unit, because mine has the notorious broken screw hole for the cap screws. Not sure what GM was thinking when they made them from plastic! Will i need a scan tool if i use a whole new distributor?

 

[Ginger]

no, the scan tool, isnt needed necessary, for a new distributor, but i would put a new coil on before i put a distributor in, its cheaper and easier if you take yours out, its not hard to line up a stock one, they arent adjustable, so they pop in a certain way. the computer adjusts the timing.