So, after getting my steering linkage repaired I decided to tackle my (3) incomplete monitors on the Blazer this afternoon. I found a few links directing me to the ODBII drive routine for GM vehicles and thought I'd give this a try before driving all over town trying to reset the monitors. Here's where the problem begins.

I followed the print out and drove back home to scan the vehicle for codes. I still have the (3) incomplete but I also have a new error code, P0300.

After looking through several threads explaining how picky these trucks are with secondary ignition parts, I thought I'd ask this question?

Are Champion spark plugs better than Autolite?

I ask this because I replaced the plugs when I bought the vehicle with Autolites and I never saw a P0300 code error with the Champions (which where in the truck at the time of purchase).

I know, I should only use AC Delco parts but like many others may have asked, how can a manufacturer claim a part they make will work for a specific vehicle if it really doesn't? Don't they have OE specifications to go by when producing these parts? I would like for someone to explain this to me, please. This truck is really draining a hole in my pocket.

Is there a way to check the distributor for play without taking it out of the engine? I thought I read somewhere this was an issue with someone getting the same error code.

No offense, by my Ford isn't nearly as picky as this Blazer and I've been able to use just about any brand of spark plug on it and never had any ignition issues.

 

These trucks run the best on OEM plugs, caps, rotors, fuel pumps, fuel pressure regulators etc. Going cheap doesn't work anymore.
So to answer your question NO. The right plugs for these trucks are AC Delco Platinum plugs. They are around $6.50 EA. from Auto Zone.
A PO 300 is a random multi cylinder misfire, which can be caused from many different things.

 

you can also use ngk plugs (im using ngk v powers,awesome plugs),and copper ac delco's,the platinum last much longer though.

 

Check with us here first, and your wallet won't get quite as light
AC Delco 41-993 with a gap of .060"
Set an Autolite, a Champion, and an AC Delco plug next to each other, look very closely at the taper seat and the porcelain insulator for the center electrode, they are all different. Chrysler, use Champion plugs. Ford, use Autolite or Motorcraft. GM, use AC Delco. As for why the Ford isn't pickey.... it's a Ford I worked in a Ford dealer for 20 years, I'll never own one. As for checking your distributor bushings... the only accurate way to check the bushings is on an oscilloscope. For what you'd pay someone to check them, you can buy a new distributor. Don't waste your time or money on a plastic distributor, get one with an all aluminum housing.