changing spark plugs

how do i get to the plugs in the back of the engine of a 3800 ? it is on a buick regal.

For '97 and up Regal it is tedious but not that big of a problem. It is not necessary to undo the engine mounts and rotate the engine like alot of people suggest. All that does is add more time to replacing all the spark plugs and/or wires. I've never been able to figure out why people do that.

For tools all I use is a 3/8" spark plug ratchet which has an articulating head, a short extension and the 5/8" spark plug socket. The most difficulty I've experienced is getting the wire boots off the plugs not accessing or removing the plugs. I use dielectric silicone grease and coat the tips and ceramic of each plug from now on for any future plug removal.

To remove rear plugs I remove the strut cross brace, undo the front 02 sensor wiring harness from the rear bracket, remove the 02 sensor from exhaust, remove the bracket where 02 sensor harness clips to. Two 13mm nuts hold the bracket onto the exhaust manifold. That gives plenty of room to remove the rear plugs #2, 4, 6. I've done all spark plugs to include wires in my Regals in two hours or less and have never rotated the engine forward to do so. For the 02 sensor removal, Autozone sells the 02 sensor socket.

BTW - Be sure to use OEM AC Delco spark plugs like the 41-101 Iridium or 41-921 Platinums. If you are cheap like me I found that Autolite AP 605 Platinums work great. Walmart has them for around $3.70 for a two pack. Do not use Bosch. Also, depending on your mileage changing out the wires is a good idea. Stick with AC Delco Premium Silicone 7mm wires and you can't go wrong. Good luck!

I have never taken my O2 sensor out. But thats on my gas guzzling pontiac GP :eek7:

Troy

I have never taken my O2 sensor out. But thats on my gas guzzling pontiac GP :eek7:

Troy

I do it so I don't inadvertently damage it. The rear plugs have a tendency to cause frustration and raise temper levels. Thats why it is a good idea to have a few brews before, during and after. :lol: On the Regal the darn thing lines up perfectly with the #6 spark plug. While the sensor is out I clean the carbon off it and make sure I can see daylight between all the vanes. I guess we all have our own ways of doing things.

Yea its real close but with a little finesse you can get #6 out. I would agree with the brews! :bigthumb:

For '97 and up Regal it is tedious but not that big of a problem. It is not necessary to undo the engine mounts and rotate the engine like alot of people suggest. All that does is add more time to replacing all the spark plugs and/or wires. I've never been able to figure out why people do that.

For tools all I use is a 3/8" spark plug ratchet which has an articulating head, a short extension and the 5/8" spark plug socket. The most difficulty I've experienced is getting the wire boots off the plugs not accessing or removing the plugs. I use dielectric silicone grease and coat the tips and ceramic of each plug from now on for any future plug removal.

To remove rear plugs I remove the strut cross brace, undo the front 02 sensor wiring harness from the rear bracket, remove the 02 sensor from exhaust, remove the bracket where 02 sensor harness clips to. Two 13mm nuts hold the bracket onto the exhaust manifold. That gives plenty of room to remove the rear plugs #2, 4, 6. I've done all spark plugs to include wires in my Regals in two hours or less and have never rotated the engine forward to do so. For the 02 sensor removal, Autozone sells the 02 sensor socket.

BTW - Be sure to use OEM AC Delco spark plugs like the 41-101 Iridium or 41-921 Platinums. If you are cheap like me I found that Autolite AP 605 Platinums work great. Walmart has them for around $3.70 for a two pack. Do not use Bosch. Also, depending on your mileage changing out the wires is a good idea. Stick with AC Delco Premium Silicone 7mm wires and you can't go wrong. Good luck!

Great advice but disconnecting the dog bones for folks with big meat hooks IMHO works best. No O2 sensor removal makes getting those stubborn wires off easier, much more room to play with #6 which makes it easier, no cut up hands and can do the rears in less than 30 minutes with less than 10 to reattach the dog bones. More room to operate just makes the job easier. Do be careful around the O2 sensor though, it does have sharp edges.

Great advice but disconnecting the dog bones for folks with big meat hooks IMHO works best. No O2 sensor removal makes getting those stubborn wires off easier, much more room to play with #6 which makes it easier, no cut up hands and can do the rears in less than 30 minutes with less than 10 to reattach the dog bones. More room to operate just makes the job easier. Do be careful around the O2 sensor though, it does have sharp edges.

I've got medium sized meat hooks and it works fine for me. :lol:

Removing the 02 sensor is easier than removing spark plugs plus while it is out service such as carbon removal can be performed on it.

Sharp edges on an 02 sensor? I don't have any. 02 sensor sockets (universal) are readily available at stores like Autozone for around $9 and make the job a breeze.

Hi bnaylor3400. What are you using for the O2 sensor cleaning?

Hi bnaylor3400. What are you using for the O2 sensor cleaning?

Hi. I use STP throttle body spray cleaner. Some people use fuel injector cleaner. Important thing is to make sure the vanes have no imbedded carbon when you hold the 02 sensor up to light and observe each vane. Each should have a clear opening. Good luck!

I just sucessfully changed the spark plugs in my 93 3800 regal :grinyes: It runs soooooooo much better.

When doing the change on the back side the #6 plug was the easiest. I couldn't find an o2 sensor anywhere. The other 2 plugs weren't hard to remove as well. I did bash my middle finger knuckle all to hell off a screw on the fire wall though.:banghead:

I would really like to know where to find the o2 sensor as I would like to clean it before summer. Also, I only had 1 dog bone mount to undo. Curious as I want to know if I have some special set up. Thanks for the help.

I just sucessfully changed the spark plugs in my 93 3800 regal :grinyes: It runs soooooooo much better.

When doing the change on the back side the #6 plug was the easiest. I couldn't find an o2 sensor anywhere. The other 2 plugs weren't hard to remove as well. I did bash my middle finger knuckle all to hell off a screw on the fire wall though.:banghead:

I would really like to know where to find the o2 sensor as I would like to clean it before summer. Also, I only had 1 dog bone mount to undo. Curious as I want to know if I have some special set up. Thanks for the help.

I posted this reply a few days ago and just want to know if someone can give me some answers. Thanks

I posted this reply a few days ago and just want to know if someone can give me some answers. Thanks

On the Series I 3800 you should have two 02 sensors. One before the CAT convertor and one after it.

Not sure exactly where it is located on your model but my reference material says the Position 1 02 sensor is in the area of the exhaust manifold.

Referring to the 93, only one sensor ,at the upper part of the engine pipe near the exh manifold. Bob correct me if I am wrong.

Referring to the 93, only one sensor ,at the upper part of the engine pipe near the exh manifold. Bob correct me if I am wrong.

Max, I really don't know. I responded because no one else with his year model Regal did. My AC Delco listing shows two different 02 sensors for his year model. I see position 1 but not position 2. AC Delco shows two distinct part numbers. It beats me why it shows two 02 sensors but it will be quite obvious the one he is looking for is on the exhaust system (rear bank area towards firewall).

Thanks guys, I will go looking. I will post when I find it or both.

Thanks guys, I will go looking. I will post when I find it or both.