How do I change the spark plugs in a '04 Chevy Impala (3.8)?

impala
chevrolet

#1

My dad has a Chevy Impala 2004 v6 3.8 and want to change the spark plugs and wires. A shop quoted him $325 to do it. I can get the parts for $60. I am a shade tree mechanic and do most of my own work but have not done plugs on this car. Is it a very difficult job and do I need any special tools?

Thanks, Albert


#2

I think this is the engine that’s a real pain to change the plugs on…The plugs aren’t accessed easily…You have to remove several parts just so you can see the plugs and wires.


#3

to find out which parts and what order to remove them and reinstall them, get a Haynes or other repair manual, it will also tell you how to diagnose the condition of the plugs. Check with the dealer to see if you need to change these plugs, as some of the newer engines have very long lived plugs, up to 100k miles.


#4

Most of these 6 cyl engines are a total PITA. Some worse than others.

What I would do, in addition to the Haynes manual, is find one of any number of Chevy forums. I’ll bet there are ones dedicated to the Impala, and I’ll bet that within those there are plenty of threads on how to deal with it.


#5

The V6 is mounted transversely. That makes the front 3 plugs relatively easy to see and work on. It is the back three plugs that are the problem. Get the hood up and see if you can find and see the back 3 plugs. If yes, you have a chance. If no, then you need to get manual to find out what has to come off to get access to the plugs.

If you decide to try it, start with one of the front plugs. See if it comes out easily with no surprises. How much wrenching pressure did you need to take it out etc? Then go the back plugs and see if you can get one out. If it turns into a nightmare, button it up and have dad pay the mechanic to do it.


#6

I can accept that it needs plugs without too much dialogue but why the wires also, planning on damaging one during plug replacement?