Changing Spark Plugs on a 97 GP

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. :banghead: :crying: I have searched and did not find any threads pertaining to any procedures to remove the spark plugs and wires.:1zhelp:

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

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.

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.

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.

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

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 :smile:

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.

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 :smile:

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!

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 :banghead: just to save a few pennies. :mad: 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. :crying: :mad: 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.

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.

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.:grinyes: :smile:

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

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.


http://i5.photobucket.com/albums/y186/lizzywiz/DSC04236.jpg


http://i5.photobucket.com/albums/y186/lizzywiz/DSC04240.jpg

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.

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.

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.

Try either disconnecting the exhaust before the converter, or removing the oxygen sensor in the rear manifold to give the backpressure somewhere to go. If it runs better (albeit louder), then you have a clogged/bad converter.

I know that I had a Dodge Champ that the cat clogged. Dodge would not cover the cat under warranty due that there was droplets of led on the top of the honeycomb. The car was back firing and would not drive over 30mph. The GP will run at speeds over 65mph. So I believe that the cat is not clogged.

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!

the wishbone puller? it does too work on the 97-03 grand prixs. i just changed the plugs on my GT 2 months ago and used the tool. also used it on my SE last year when the plugs were changed. maybe we are talking about 2 entirely different tools?

the wishbone puller? it does too work on the 97-03 grand prixs. i just changed the plugs on my GT 2 months ago and used the tool. also used it on my SE last year when the plugs were changed. maybe we are talking about 2 entirely different tools?

Grandprixgtx00 where did you get the tool and how much was it. I would like to save my arms, hands, and my back. Do not need any more surgeries on my back. 5X was too much. Do you have a picture that you could post

Grandprixgtx00 where did you get the tool and how much was it. I would like to save my arms, hands, and my back. Do not need any more surgeries on my back. 5X was too much. Do you have a picture that you could post

I'll try and find a pic or somethin. my dad owns an automotive shop so i actually used his. if im not mistaking he got his from Matco. I'll look around real quick though.

here is a link (http://www.etoolcart.com/browseproducts/Engine-Tilter---THX419X.HTML) to a website with a pic of the tool. looks like they want $56.00 for the tool. let me tell you though...it makes the job MUCH easier! guess you could just look around and see if you can find one cheaper.

Grandprixgtx00, thanks for the info, the price is worth it especially for having to eliminate the stress on my lower back. Do not need or want another surgery on my back. Five surgeries is way to many. How many would I need? Would one be enough or do I need two.

Can anyone show me where a torque strut tool is recommended by GM, Chiltons, Haynes or other reliable sources? The GM 3.4L and 3.8L engines even with the dogbone (torque strut) engine mounts were not designed to have the engine rotated to remove spark plugs. Good way to damage the transmission mounts and other components like exhaust system. Also, use of the tool will not preclude any physical activity required to replace the plugs, doesn't give you any extra reasonable clearance making the expenditure worth the cost, and adds more time to the job. :2cents:

Can anyone show me where a torque strut tool is recommended by GM, Chiltons, Haynes or other reliable sources? The GM 3.4L and 3.8L engines even with the dogbone (torque strut) engine mounts were not designed to have the engine rotated to remove spark plugs. Good way to damage the transmission mounts and other components like exhaust system. Also, use of the tool will not preclude any physical activity required to replace the plugs, doesn't give you any extra reasonable clearance making the expenditure worth the cost, and adds more time to the job. :2cents:

i am definatly not going to argue with you...because obviously you have way more knowledge than i do. however my dad is master ASE certified and i'm sure he knows what he is doing. i highly doubt he would use a tool on my car that would ruin it. I am telling you, this tool made the job MUCH easier. again...not arguing or anything, because i have much respect for you.

Grandprixgtx00, thanks for the info, the price is worth it especially for having to eliminate the stress on my lower back. Do not need or want another surgery on my back. Five surgeries is way to many. How many would I need? Would one be enough or do I need two.

you only need one. undo one wishbone motor mount, and hook up the puller then remove the other motor mount, and pull the motor forward. again...you will want to make sure the trans axle is in neutral before pulling the motor forward.

I am telling you, this tool made the job MUCH easier. again...not arguing or anything, because i have much respect for you.

How does it make the job easier or any faster? By the time you connect it and do the racheting you could have at least 2 of the 3 rear bank plugs out. The best thing to do is use the right spark plug removal tools and have patience. The tool will not make getting the rear plug boots off any easier either. I've never had an issue replacing the rear bank plugs the conventional way. Regardless, moot issue for me since the tool will not work if you have headers installed.

The last person with a stock Grand Prix GT I worked with that used a similar tool wound up ruining the tranny mount which was a real PITA to replace. The rubber insulating part of the mount broke in half. The symptoms were a vibration feeling in the steering wheel and dash, the exhaust knocking on the bottom of the body and a knocking sound when accelerating. So my advice is use the tool at your own risk.

Yeah, Bob, I dont even think the newer 3100's can be rotated forward. I think that tool is pretty much just for the older 3.1mpi motors where the back 3 plugs are IMPOSSIBLE to reach.

just use a large flate blade screwdriver and a small vice grips to pry the plug boots off, and the proper 3/8's ratchet and extensions with a spark plug socket, and you shouldnt have any problems getting te back three plugs out. A spark plug swivel socket might be helpfull for the plug thats right behind the O2 sensor, but it is very do-able.

Well I guess there is pros and cons of using the tool to rotate the engine. Also I am wondering since I need at least one coil pack. Should I just replace all three coil packs :1zhelp: . I have a friend that has three OEM coil packs that he will sell them to me for $25 each. Which I know is a very good price.

It is up to you. But it doesn't make sense replacing parts or wasting money unless the parts are confirmed bad. How did you confirm you have a bad coil? Did you swap them out with one another? Have you checked coil primary and secondary resistance with a multimeter (DMM)?

Ignition coil primary resistance = 0.5 to 0.9 Ohms
Ignition coil secondary resistance = 5K to 10K Ohms

The primary for cylinders 6 and 3 the primary is open, and for cylinder 5 and 2 the primary is also open. Have not checked 4 and 1, does anyone know what size the bolt that holds the coil pack down. Need to run to Sears to get the socket. Thanks for all the help. So since there is two bad coil packs I am going to replace all three coil packs. Better safe then sorry. Even if it is not bad that will give me a spare.

I think that it is 1/4", so I am off to Sears to get a socket set. :smile:

At least two coils with primaries open? Were you in the lowest reading for ohms if you have a manual selector and not autoranging for the meter. Wonder it even fired up or ran. As far as bolt size not off the top of my head but for the socket size I use a SAE 7/32, 1/4" drive.



Note: To measure coil primary resistance the coil must be removed from the ICM module. Then you go across the two spade contacts you see.

I had the meter set to the lowest setting. Now I need a new battery, not holding a charge. So I will let you know if the car runs with out the P0300 DTC. Originally I was getting a random misfire on cylinder 6 and 2, when I would get into the gas. So I did the plugs and the wires. Letting the battery charge up now. Will try starting the car and see if the idle is smooth. From what I measured, I should be good to go. I bought a 1/4" socket set and I knew that it was 7/32 bolt. I was thinking about buying just the one socket, but it was around $3 so I decided to buy the complete set for $19. The wife is back to work for the rail road, money is not as tight when she was off. Thanks for the reply.

Well after replacing the two coil packs for cylinders 6 and 3 and cylinders 4 and 2, the car is now running very good. Did not have to replace the battery, found that the positive connection on the battery had some corrosion causing the resistance to be high between the battery connection and the battery cable. I am still going to replace the last coil just to be on the safe side.

When you pull the spark plug boot from the wire end, it causes the opposite end to close tighter around the plug body. A spark plug boot removal tool allows you to pull the boot from the plug end, and makes it easier to remove the boot without damage. You can purchase a tool from the following the site:
http://taeckertindustries.com/prod05.htm

The problem was that the dielectric grease dried up making it very hard the getting the boots on the back, to release from the spark plug. I always pull the plug side first. That way I can route the wire back to the correct coil. The front side broke apart and I was replacing the wires anyway.