Replaced plugs and wires, but still has a skip.

If the skip remains after warm up it's probably ignition, replace that cap and rotor.
If it goes away once warm it's probably too lean while warming up, start looking for vacuum leaks. Plenty of places for this on that engine.

 

UPDATE**

I haven't had a chance to replace the cap and rotor, but might try and do it this weekend. In the meantime, I went thru my original notes from when I first saw the vehicle and ran the engine. There was no noticeable skip that I could recall, but I did notice the MAP sensor was unplugged along with a couple of unhooked vacuum lines. I began hooking everything up along with the MAP sensor and took the car to the local car wash to steam clean the engine. I did not power wash the distributor area, but did spray the rear firewall to degrease it.

Then, I plugged in the MAP sensor and drove the car up north and noticed the skipping/missing. The CEL code was 34 for the MAP since this engine is pre-Mass Airflow Sensor. I ordered the sensor and will be replacing that along with the cap and rotor. I posted a separate thread about my dad's go-to mechanic who in my opinion does not want to hassle with properly diagnosing the poor running of the engine and recommended a rebuilt unit along with a rebuilt trans (no noticeable issues with the trans) for $6-8K. Seriously?

I know the MAP sensor works off the engine vacuum to send a signal to the ECM. I told my dad to unplug the MAP sensor and start the engine and see how it idles, but he is busy getting ready to host Monday.

I will post my results after I replace the cap and rotor and sensor and possibly pull the valve covers to check the status of the rockers and valves for any obvious signs of something loose or broken.

 

If it was a Ford, the engine would barely run from extreme richness with an unplugged MAP. Also, if vacuum lines are unplugged, that will lower the vacuum signal, which will throw off the MAP. If you had a scan tool that has live data, you can check what the MAP reading is. Around 10" is a good running engine at sea level, and MAP reading plus vacuum gauge reading equals barometric pressure, when the intake system is properly sealed.

 

Don't overlook a plugged up PCV system, valve or hoses.

 

Could be a cracked cap. Start it up, when cold, in the dark (outside at night). If the cap is cracked you'll see light flashes. When It warms up, the heat closes the crack...Good luck

 

I posted my repair results on my other thread. I replaced the cap and rotor this weekend and found another broken vacuum line to the MAP sensor base. I still need to double check the PCV valve and possibly replace the fuel filter again, but the car runs a whole lot better and smoother. I am sensing a ticking on the passenger side (metallic) but the engine doesn't "surge" at idle like it did before.

Looks like I'm on the right track to dialing this motor in. It's either going to be a collapsed hydraulic lifter, loose rocker or rod bearing. Let's hope its one of the first 2!!

Will post after he puts some miles on the engine to work out some more kinks.

Ted

 

I've lost a couple of rod bearings over the years. There is a distinct difference in sound between worn rods and lifters imho.

 

Rod bearings "knock". A tick is a lifter or rocker. Pull off the valve cover and check the rockers on each cylinder with the valves closed. See if any need adjustment. You might get lucky.