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please help


trick tee
08-29-2014, 06:43 PM
heres the deal i have a 1996 chevy caprice wit a 4.3 v-8 one day i was driving and the car started acting funny and the check engine lite started blinking i had the codes read and 0p300 came up saying multiple misfire so i changed the plug wires they all connect in the front around the harnonic balancer well that didnt work its still saying mult misfire so i took a spark plug wire of of the electic dis block and no change in motor now i dont no wat to do can anybody help me solve this problem

Blue Bowtie
08-30-2014, 07:18 AM
It may be a failing OptiSpark cap and rotor. The insulation of the Opti can break down, causing cross-firing of plugs and misfire.

j cAT
09-01-2014, 04:16 PM
heres the deal i have a 1996 chevy caprice wit a 4.3 v-8 one day i was driving and the car started acting funny and the check engine lite started blinking i had the codes read and 0p300 came up saying multiple misfire so i changed the plug wires they all connect in the front around the harnonic balancer well that didnt work its still saying mult misfire so i took a spark plug wire of of the electic dis block and no change in motor now i dont no wat to do can anybody help me solve this problem

could be the OPTI distributor BUT I would first check the fuel pressure key on engine off the GM spec is 41-47 PSI, ............lately many have had in tank fuel pump wiring issues.. If you drive around on E that will do it...that being good then you look very carefully for any coolant leaks on to the opti ... you look for any oil leaks at the opti these kill the opti causing miss fires. next is the venting vacuum harness. if that is some how disconnected or damaged [bad vacuum line ] the opti cap /rotor gets damaged from the ozone gases created from the arcing contacts..
the other problem with these as they age is the opti rotor bearing. these wear out at around 100K miles the rotor will wobble and cause misses...

most times because GM mounted the opti distributor under the water pump weep hole this is how they get damaged. I installed a weep hole drain hose so that it will not weep coolant into the distributor 18 years ago.

If the distributor is bad now you have a problem of getting a new one. a new GM distributor goes for 400-500 USD.. advance auto has a NEW cardone one for 225 USD with a good warranty ... replacing is not hard but very time consuming and many shops are unable to make these repairs properly .... I did my opti last year .took 8 hrs. but it still works perfectly and no leaks ..p0300 would not be plug wires. hard to do those wires with the water pump on there..

good luck...

trick tee
11-19-2014, 04:47 PM
I was plugs n wires It was running good but now I have a new problem wit this Caprice

j cAT
11-20-2014, 04:24 PM
I was plugs n wires It was running good but now I have a new problem wit this Caprice

what plugs and wires did you have in this that caused the P0300 code ?

bad PLUG wires will damage the ICM

Tech II
11-21-2014, 03:55 PM
May we ask what the new problem is?

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