I need to change the plug wires, plugs, cap and rotor in my 2002 ZR2 Sonoma. I've got the cap and rotor figured out, but MAN the plugs and wires are going to be a bear! How can you access the little clips to hold the wires??? The passenger side seems do-able, but the driver side is BURIED! can I easily remove anything for better access???

Here is a link for how to change #3 plug. http://www.automotiveforums.com/vbulletin/showthread.php?t=503231

If you raise the front of the vehicle and let the wheels hang, you can access some plugs through the wheel opening. The rest are done from the top.

I used after market cap, rotor and wires, it wound up dead after severe rain while on vacation had to have towed to GM Dealer who replaced the cap. They said it was common with after market caps not sealing.

Thanks for the tip about the steering shaft, it was very helpful. Now I am continuing to have the problem I was trying to fix even with the new plugs, wires, cap and rotor...

I was having arcing at the plug boots w/ old parts, I figured it was worn/cracked boots on plug wires. Now, I have replaced plugs, wires, cap and rotor only to continue having this arcing! My codes have been P0305, P0306 and P0300 (mostly P0306). Upon darkened inspection, I can see arcs randomly from the wire boot right to the heat shielding that lines the exhaust manifolds near the plugs... I have tried bending the heat shielding to be farther away from the boot surface, but no change.

Any ideas???

Thanks!

-john

What brand of parts are you using?

Yes, the parts are Duralast wires, Bosch plugs, Niehoff rotor and caps.

Bosch plugs are no good in the 4.3L If you search Bosch plugs in the Blazer forum you'll find many negative posts about them. Use A/C Delco platinums ONLY. Niehoff cap and rotor are acceptable, but not the greatest. Duralast wires are a "low quality" wire, as you've confirmed by the arcing. A/C Delco or Autolite professional series are the best. Did you use silicone dielectric grease on each end of the wires when you installed them?

Ok, I will swap the plugs to your recommendation, Thanks!

As for the wires, the boots had some grease inside before I snapped them on the first time, but over the course of troubleshooting I have removed and reinstalled each wire many times... Maybe more silicone dielectric should be added? If not, new plug wires?

Thx...

You can put make up on a pig, but when you're done, you still have a pig. Exchange them for some good wires, you won't regret it.

OK, I have swapped the bosch plugs for OEM ACDelco Platniums. And, have returned the Duralast Wires and installed AutoliteProfessional wires, with dielectric grease on both ends. I don't see anymore arcing from boots, but it's still reporting random misfiring. (P0300 and sometimes P0306). And, of course, the idle is still rough like it's missing.

The spark is fat and strong as far as I can tell. (I pulled a wire and hooked up an old plug and ran the motor to see the spark.) I can "hear" snapping somewhere I think, but it could just be random engine noise.

Could this be the distributor itself?

It's possible that the distributor bushings are worn, but without specialized test equipment, you'll never be able to confirm that's the problem. If you hear a snap, you might be hearing spark arcing somewhere. Take a spray bottle with water and direct a mist over the distributor cap, ignition coil and wires, especially #6, (rear plug passenger side). If you do it at night, the arc will be much easier to see. Post your findings.

Ok, after days for chasing my tail w/ ignition issues... I took it to be diagnosed @ Midas. They said it isn't ignition at all, that it's the injector assy. Seems to make sense now that I realize the fuel is delivered separately to each cylinder, not just to an intake manifold common area like I thought.

Thanks for the help along the way though. I was certainly having problems with the duralast wires and Bosch plugs too.

Until next time..

-john