Alright, I've got a 96 S-10 4x4 with a 4.3LV6 vortec in it... It was previously my brothers, now its mine. Check engine light has been on for awhile and I cant drive it until it gets insected, wont pass with the light on...so we ran the codes came up Random/Mutiple Cylinder Misfire. Its got brand new plugs and wires, and we swapped the cap and rotor. And its sometimes hard to start, but most times it starts up after after 2-3 second crank, and it idles around 900-950rpm, and as its running the whole truck sorta rocks back and forth... and the CE light is sometimes solid and it sometimes blinks if that matters at all... I know some stuff about cars but definitally not enough to work on stuff myself yet but I'm learning.

 

how did it run b4 doing above named mentioned parts?

 

It ran the same really. My brother did the plugs about a 7 months ago, but between now and then he got incarcerated lol so its been sitting for awhile but the plugs and wires only have about 600 miles on them and I pulled them to take a look and they look perfectly fine. He had the same problems but ran it anyway cause he couldnt figure it out and didnt have the time. As for the cap and rotor, my dad saw some white powder on the cap(i guess from the sparks) and decided to replace them anyway but they were brand new too, and its wired correctly.

 

AC Delco plugs, GM original spark plug wires or better, and OEM cap and rotor or better. Anything else and it will run like crap.

Run a can of seafoam through the gas tank and check the air filter. Sometimes its the simple stuff.

P0300 is the worst code to get. To rule things out, install the best parts, especially the ingnition system. These are high performance engines and will eat cheap ignition parts in a heartbeat. 600 miles noda. I drove mine for 9 months before the cheap crap died.

 

The white powder you see inside the distributor cap isaluminium oxide from the aluminumelectrodes in the"made in Mexico" AC Delco distributor cap. Install a NAPA ECHRR241 distributor cap and matching RR241 rotor with brass electrodes. The cap isblack just like the AC Delco cap and you can tell people it is a "Genuine AC Delco" part.AC Delco parts ain't what they used to be. I installed a AC Delco master cylinder an it was made in Italy which is not much better thanthan Mexico. The AC Delco ignition wire and spark plugs aregood products.The spark trackingin the distributor cap because of the aluminumoxide would not become a problem for at least 7,000 miles and would not be severe enough to cause what you describe. Spark trackingis more of a problem if incorrect ignition wire is used.

Keep looking at the ignition system because 85% of engine miss problems are electrical in nature. Make sure you installed the goodparts. Here are the parts you should use:AC Delco AD1943A distibutor module -$50.00, AC Delco coil - $44.00, AC Delco D577 ignition coil - $45.00., AC Delco 746T ignition wire - $70.00, AC Delco CR43TS spark plugs gapped at.035". If those parts do not fix the problem,you have a fuel delivery problem. Sometimes the fuel pressure regulator will give trouble..and the GM partcosts at least $500.00 whichincludes the CPI assembly.Aaftermarket fuel pressure regulatorcan be replacedseparately from theCPI assembly, Dorman #55162 - $37.00

 

I do NOT recommend the NAPA Echlin cap & rotor. I installed a set, but for the 93, and they were toast in 150 miles. The second set, replaced under warranty, lasted less than 100 miles.

I installed a NAPA cap & rotor and haven't had any trouble in the 1000 miles since. YMMV

 

NAPA Echlin caps have brass electrodes just as all good quality caps have. Besides aluminum oxide contamination, what could go wrong with a cap and rotor in less than 100 miles? What does toast mean? Did it break? Please elaborate and I may not buy one.

Even with an regular production OEM AC Delco or a aftermarket replacement rotor and cap with aluminum electrodes, it would take at least 3,000miles for the aluminum oxide dusttocausespark scatter.The NAPA Echlin caps are more expensive than the NAPA regular replacement cap that hasaluminum electrodes but for some strange reason, the higher the price the better the product.

Accel sellsa blackdistributor cap with a thickeralklyd distributor cap andbrass electrodes but it is only offered for a 1995-2004 S/T-10 Blazer 4.3L V6.......$50.00.

All Accel high performance distributorcaps have brass electrodes and a thicker alklyd cap. I have used those quite oftenon 1957-1970 transistorized and point typeGM distributors but I cannot tolerate the aftermarket tan appearance on a restored vehicle. Unfortunately, the bestAC Delco distributor caps for 1957-1970GM V8 distributorsare long gone. They had copper electrodes and were first introduced forCorvettes and were used on otherGM high performance vehiclesfrom1960 through the early 1970s. The were designed to be used with Delco-Packard 440 stainless steel ignition wire before TVRS became a perceived problem on street driven vehicles.I bought four of those AC Delco caps for $15 eachin 1989. They were discontinued about 1980. Now, I seethose 1957-1970 AC Delco high performance distributor caps sell for $150 each at swap meets and on e-bay. There is one of those rareAC DelcoV8 distributor capson e-bay at this minutethat has a "Buy It Now" price of $175.They could be identified by their dark reddish-browncolor, copper electrodes and DELCO REMY embossed aroundthe center coil wire post.