I gave my 95 Blazer a tuneup today. I replaced the distributor cap and rotor, plugs, and plug wires. Everything's AC Delco except for the plugs; I went with E3 for those. I was able to replace the #3 plug with just a wobble extension, too; didn't have to pull the steering shaft - and didn't even have it turned the right way (with the flat side on the bottom to let the extension pass straight).

It runs like crap and smells rich. I have a MIL, too.

Okkay, fine. I whipped out my shiny new AutoXray 6000 scanner, hooked it up, and told it to scan. It did. It dutifully told me the MIL is on - and that there were no trouble codes for it to report. It's an OBD-II truck. I have the scanner set to a 1996 model. Setting it to 1995 and using either the yellow or blue cables complains that it's not communicating with the vehicle.

Now what?

 

sounds like you either mixed up a wire or two or the rotor was put on 180 degrees from where it should be. i would double and triple check your spark plug wires and if they look fine then pull the cap off and unbolt the rotor and turn it 180 degrees and bolt it back down. heres the firing order...... 1-6-5-4-3-2, clockwise rotation.

 

The cap has the cylinder numbers molded into it. (Good going, AC Delco!) I traced the wires out and made sure they went where they should.

My suspicion is that one of the plug wires isn't fully seated at the plug, and I'll check them tomorrow morning after the engine cools down. It would have been nice to know which one, though, without having to pop them off.

If the rotor was off 180 degrees, wouldn't it not run at all? In any case, I made a note of where the rotor was pointing before I took it off, and I put the new one on right away, so I doubt that's it.

 

Wasn't the wires at the plug. I unplugged them all and reseated them, making sure they all went "click" when I pushed them on. Still ran rough. Wiggling the wires didn't change the condition. It'd *really* be nice to know which cylinder wasn't firing properly.

Also, is it possible the computer needs resetting? The old plugs looked pretty ratty when they came out...

 

I'm having the same issue but mine started after a motor swap . I'm taking mine to a shop to have a new computer flashed . Hope it works .

Mines getting spark and fuel but is only running on #1, #5, and #2.

 

I could have sworn I'd traced out all of the wires...but I checked again, and 4 and 6 were reversed at the distributor. Swapped them, truck runs fine.

 

lol, glad you got it fixed!