Screech!

[M. Murphy]

98 base: cleaned and re lubed starter and replaced bearings (6302) on the upper and lower pulleys per Ben's Burners, new poly rib belt 2k ago. The starter caused screech is gone however occasinally I'll get a short one when the engine comes off idle. The water pump has 49k on it but spins freely by hand, very smooth with extremely slight endplay est < 1mm. Any thoughts by the brain trust? Thanks

[JFP in PA]

Check your spark plugs for torque, leaking plugs can make screeching sounds.

[M. Murphy]

Thanks, I would not have thought that.

[M. Murphy]

Okay, retourqued the plugs to 22'lbs per Bentley. Everything back together and I have rough idle and running. My suspicion is a bad coil pack connection, is it okay to disconnect the suspect coil pack and start the engine without damaging something?

[JFP in PA]

Originally Posted by M. Murphy

Okay, retourqued the plugs to 22'lbs per Bentley. Everything back together and I have rough idle and running. My suspicion is a bad coil pack connection, is it okay to disconnect the suspect coil pack and start the engine without damaging something?

It is never a good idea to purposely run an engine with a dead hole, but a short run should not hurt anything.

[M. Murphy]

I'm thinking the connection on the rh rear plug just would not click together like the rest.

[M. Murphy]

"The world is once again running in greased grooves". John Ford narration in Cannery Row.
Swapped coil packs and she runs great!

[M. Murphy]

Well, seems I spoke too soon. Tried a short drive and found a mildly rough idle with roughness through the rmp range. Changed to new plugs (Bosch 7402) since that was coming due. Everything connected and torqued. No access was made to the engine from above and the only thing different was I tried to clean some oily grime off the right aft corner of the engine with carb & choke cleaner scrubbing with a parts brush.
Could this be a coil pack failure?

[JFP in PA]

Sounds like it. Pull the coil packs and look for cracks, no matter how small. Once that starts, they coils are done.

[M. Murphy]

Thanks, I was about to button everything up, put the wheels on and go on another tack: I was going to go after the throttle body and MAF.

[M. Murphy]

Just pulled the coilpacks and it looks like I'll have to replace them. From the drivers side. Bottom, from the passenger side. The cracks in the black material seem to be in the mounting boss area.

[JFP in PA]

Originally Posted by M. Murphy

Just pulled the coilpacks and it looks like I'll have to replace them. From the drivers side. Bottom, from the passenger side. The cracks in the black material seem to be in the mounting boss area.

Those are way past being done. Common failure point.

[M. Murphy]

I've decided to replace the O rings on the spark plug tubes while in there replacing the coilpacks. The tubes are turning out to be a challenge to remove. In order to avoid damaging the tubes I have modified a 1" expandable drain plug described on Pedro's website and I still can't get the tubes out. Is there a trick to this?
Thanks.

[JFP in PA]

You have to watch out as the tubes can become brittle with age, so you don't want to go nuts here as you could shatter a tube, which would require pulling the cam cover.

We use a set of battery terminal pliers, with the heads inside soft rubber tubing to grip and twist the tubes to pop them loose:

[M. Murphy]

Thanks, that looks like it would work. I've seen some online videos with different ideas, should find something that works. Number two is the only one I've tried so far.

[M. Murphy]

Decided to forego tube removal, tried#1 and 2 two different methods and could not budge them, almost like they were glued in. Looked back in the maint history, many spark plug changes over 234k miles but not one tube change. No leaks.

[M. Murphy]

Update! The rough running/misfire has been resolved. This morning I pulled and examined the connectors on all coilpacks expecting to see one connector with at least one distorted female contact. All contacts appeared identical but the right rear (#3) had not been positively locked in place. Fixed and now she runs fine.

[JFP in PA]

See? It is not all that complicated...………..