99 Blazer 4wd - Mild Miss....

[dougg01]

So, in the interest of not replacing everything in hopes of finding the actual problem.....since I don't really have the $$$$ to spare:

 

Mid rpms under load there is an intermittent miss. It's probably there at higher rpms, but I don't perceive it.

 

Could it be:

plug wires (they look decent in a causual inspection, but are of unknown age and I haven't checked ohms).

cap and rotor (haven't had the cap off yet)

Crank position sensor (someone on another board mentioned that to me as a possible cause).

 

So....using your best SWAG, where should I concentrate my efforts for the most-likely resolution. Eventually all of it will probably be replaced, but I'd rather not right now.

 

TIA :biggrin:

[Draenor]

When was the last time it was serviced?

[dougg01]

When was the last time it was serviced?

 

Define 'service'...?

 

Previous owner had all his regular maintenance done at a reputable shop, but I can tell they weren't as meticulous as I am about stuff.

 

I don't know when the ignition parts were last changed. I did the plugs a couple weeks ago when I first started driving it.

[bill190]

In the interest of saving money...

 

I would check each spark plug wire with an ohm meter. See if one or a couple are different from the others.

 

And here is a different test for spark plug wires...

http://www.trustmymechanic.com/auto-repair...plug-wires.html

[C6Racer]

What spark plugs did you use? GM engines seem to hate anything but OEM replacements. I tried using Bosch Platinum +4 plugs on my dad's old '99 K2500 Sierra with the 7.4L... BIG mistake.