Changing Spark Plugs on a 97 GP

[doctorhrdware]

I am at a stand still. I am not able to get the plug wires off of the back 3 cylinders. My arms just do not have the clearance to pull off the wires from the spark plugs. I have searched and did not find any threads pertaining to any procedures to remove the spark plugs and wires.

[BNaylor]

We have plenty of old threads on the subject. But welcome to the club and don't feel bad.

The rear bank spark plug wires can be a real PITA. Just carefully use small vice grips and/or pliers and grab and twist and pull the exposed part of the plug boot but be careful not to damage the metal heat shields if still installed. Depending on how old the ignition wires are best to replace them when doing the spark plugs. Reason is one or more wires will probably get damaged during removal and you may experience misfires later. If you get them off intact then be sure to use dielectric silicone grease which will help with future removal. Good luck!

Note: Not sure if the auto parts stores have them but GM auto techs use a special GM J tool.

[doctorhrdware]

I am already one step ahead of you, I am replacing the wires. Yes the heat shields are on the wires, I am thinking about cutting the wires on at a time and see if I can pull the off of the spark plug.

[tblake]

try and get a flathead screwdriver in there. Gently pry outward on the bottom of the blug boot.

As Bob stated, do not damage the metal heatshields. Many people think they are whats holding the boots on the plugs, but they are not.

[doctorhrdware]

Well I have gotten two of the three plug changed on the back side of the engine. Cylinder 6 is turning out to be the real PIA to get the plug out. It is so dam close to the O2 sensor on the exhaust manifold. Any other ideas would be appreciated. I am trying to be careful not to snap off the O2 sensor

[grandprixgtx00]

if you want the job to be real easy...you can just buy the tool that you hook to the front motor mounts and tilts the motor forward. makes the job 100% easier.

quick word of wise...if you decide to go this route, make sure the car is in Neutral before tilting the motor forward

[BNaylor]

Originally Posted by doctorhrdware

Cylinder 6 is turning out to be the real PIA to get the plug out. It is so dam close to the O2 sensor on the exhaust manifold. Any other ideas would be appreciated. I am trying to be careful not to snap off the O2 sensor

Remove the 02 sensor.

[richtazz]

Originally Posted by grandprixgtx00

if you want the job to be real easy...you can just buy the tool that you hook to the front motor mounts and tilts the motor forward. makes the job 100% easier.

quick word of wise...if you decide to go this route, make sure the car is in Neutral before tilting the motor forward

That tool works on the 96-older Grand Prix's, but the 97-newer models with the 3800 don't have upper torque struts, which is where the tool mounts. I use a pair of long 45 degree angle jaw needle-nose pliers to get the boots off, works great!

[doctorhrdware]

The O2 sensor, is some what in the way. But the real problem is that GM in there infinite wisdom did not use the dielectric grease just to save a few pennies. This is what is causing the problem. I am having a hard time getting the spark plug boots off the spark plugs. The spark plug boots will not turn, so I not able to pull the wires off the spark plugs that easily. My hands and arms are all cut up and bruised up. I have the 45 degree angle needle noise pliers from Sears. But because the boot are stuck on the plugs. I am going outside again now to try to get the last plug wire off.

[BNaylor]

Are these the original ignition wires? I could have sworn I've seen some sort of dielectric lube on the plug boots but that proves ineffective over a period of time and you will still have issues removing the boots. For example the AC Delco Premium Silicone 7mm OE replacement wires come precoated with the grease.

You have the original wires if they say Packard and have the cylinder numbers.

[doctorhrdware]

Yes the wires are original, but it is not the orginal engine, it is the third engine. The first two spun the piston bearnings. I finally did get the last wire off. Taking a breather. Now to get the spark plug out. That will be a lot easier then getting the wires off. The plug boots and the coil boots were dry, did not have any dielectric grease on the boots.

[BNaylor]

Originally Posted by doctorhrdware

The plug boots and the coil boots were dry, did not have any dielectric grease on the boots.

It may have looked dry but that doesn't mean no dielectric silicone grease was ever there from the factory. That stuff gets old with age and due to the high heat of that part of the engine - cylinder heads and exhaust burns off or deteriorates or drips off. The temps are well above the maximum temperature rating of any typical dielectric silicone grease. Add 10 years to that and no wonder. The stuff doesn't last forever and has to be reapplied sooner or later.

I still had the original Packard ignition wire from cylinder one that I replaced about 5 years ago in my '97 GTP. After cutting it open I could see some remnants of the original dielectric silicone grease GM used. I recall it had a greenish tint. When you touch it feels all powdery now. See pics below.

[doctorhrdware]

That is possible, well I did get cylinder 6 spark plug in. Still have the random P0300 DTC though. At least I did get the plug in before the rain started. It is just sprinkling. I think that I may have a bad coil pack. I am going to have the ignition module tested before I get a coil pack. I will see if Advanced auto can test the module.

[richtazz]

I'll assume you cleared the DTC after doing the work? If not the code will still be there for up to 50 ignition start/stop cycles.

[doctorhrdware]

Yes I did and it did return, and the idle is very ruff. I had to drive the car home with it running like this. I am wondering how long would it take to cause the cat to clog.