1997 ram 1500 threw a cylinder 8, 1, and random misfire last week. #8 plug was definitely fouled. Replaced all the plugs and realized after having a bung welded in the exhaust two years ago I never hooked the o2 sensor up. Hooked it up and the truck acted like it was starving for fuel would not hardly run underload. Come to find out the o2 sensor was mushroomed due to me over tightening it in to the anti fouler threaded into the bung. (No cat). Installed new o2 sensor and ran great for a day. Now throwing a cylinder 1 misfire code. Plug looks good. Swapped injectors today. Throws the same cylinder 1 misfire. The 97’ doesn’t have a schrader valve to relieve pressure and check it. When I broke the injector loose was a decent amount of air pressure and very little fuel came out. I’ve replaced the fuel pump when I got the truck due to sitting 12 years. Few months later plugged it up with trash from the tank. Cleaned it best I could. Could I possibly have another stopped up fuel pump. I’m stumped on this one.

 

What plugs did you install? Fixed the plenum yet? Were the plugs oil fouled?

 

Did you happen to inspect the cap and rotor? Any bad wires?

 

cheap champions from autozone $4.99 a plug gapped to .40. Plenum seems fine but I doubt it’s been replaced this is the 8 and 1 plug from initial misfire codes. Also they were ran right at 40k miles.

 

I did not. Everything was replaced 40k miles ago. Plan to swap a wire tonight and see if the misfire chases it to try and eliminate a bad wire

 

Swapping wires around was a no go. Drove about 10 miles and same code. Misfire cylinder 1

 

Your copper plugs are generally due for replacement at 30K miles.

The one is black and nasty, and looks like the ceramic is cracked around the center electrode? That's usually a sign of spark knock..... Burning oil can leave carbon deposits that contribute to knock. Wouldn't hurt to have a look in the plenum.

If you are still getting misfires on number 1...... Put your brownish colored plug in the wire, but, plug just laying on the intake or something, (re-gapped....) start the engine, and see what kind of spark you are getting there.

 

Ended up taking the anti fouler out of the welded in exhaust bung and just threaded the o2 sensor in there. Drove 22 miles to work this morning and only code I had was bank 1 sensor 2 on the o2 sensor. Which isn’t even there. Still doesn’t seem perfect. Any suggestions on visually telling if the plenum is bad? Best to just go ahead and swap to the Hughes kit or is there a better option

 

Look down through the throttle body to see if you see any oil pooled on the floor of the intake. If you see a coating of oil there, it's time to address the plenum gasket... Also, check your PCV valve to ensure it's not stuck. If you install a new PCV valve, please use a Mopar PCV valve, as it regulates PCV function much better than the aftermarket units..