I'm getting ready to replace the spark plugs and wires in my 2006 base coupe. It looks like all plugs are easily accessible, except for the one on the passenger side far rear (closest to firewall). There's a black bracket thingy positioned directly over the black rubber boot of the wire that snaps onto the plug. With that right over it, I don't see how in the world you remove that one plug and wire since there's no clearance. Also, when removing the boot from the plug, do you pull up/twist on the boot itself or the heat shield?? Any advice is greatly appreciated.

 

Make sure that the engine is stone cold before removing the spark plugs from the heads!!!!!!! If the heads are hot, bank that you are going to trip the spark plug threads out of the heads.

The plugs get gaped to .040", light coat of anti-seize on the plug threads (so the plugs are not a PITA to remove years later), and the spark plugs get torqued to 11ftlbs only.


As for the boots, grab the boot section and pull/turn at the same time to pop them off the spark plugs. If the boots have never been removed, they are going to be a PITA to remove. GM used something like ASK to install the boots so they slip on correctly with no air pressure in the boots, and when the ASK dries, it turns in to dam near a glue.

New lets back it up on the spark plugs, and they are good for 100K. So unless you engine has close to this mileage, then the plugs can be pulled to just clean them up, check the gaps, and reinstall them.

On the spark plug wires, if you can get them off without destroying them to start with, a quick check to make sure that they still have resistances, spray electrical contact cleaner to clean the boot connectors, and with some dielectric grease on the insides of the boots both top and bottom, they can be reused as well.

And a Huge Frickin note here, the higher resistance of the OEM spark plug wires, and even the OEM spark plugs are for a reason!!!!! If the resistance is too low in the wires and plugs to suppress electrical noise/spikes correctly back through the electrical system to being with, then you can end up with all kinds of problems with the car (electrical charging system with low voltage the first to rear is ugly head).


Lastly, since changing the plug and wires requiring removing the driver side fuel rail cover as well, it's best to disconnect the fuel line from the fire wall connector so you can slip the hose through the hole, instead of chancing cracking the cover by trying to wedge it open to slip the hose through that way instead.

On the front of the drivers side fuel rail, there is a schrader valve that will allow you release the fuel pressure on the rails under the black cap before pulling the line. With the gas pressure released into a cup before hand, then the braided fuel line can be popped on the solid line at the fire wall via this tool that is just a few dollars at most auto parts stores.

 

How many miles are on the car? I ask because many people on the forum have changed plugs long before the recommended mileage and found them to be just fine. Because of the love of the car, there is a tremendous tendency to do unnecessary maintenance. I wouldn't even start thinking about the plugs till at least 75,000 miles.

 

Taking the fuel rail cover off is not required for changing spark plugs and even if it was, you can get them off without disconnecting the fuel rail.

 

Thanks a lot all, much appreciated. However, I still didn't get an answer to how you go about removing the 1 passenger side far rear plug with the bracket directly over it. FYI, the car has 40,100 miles on it. I know, I know, that's way too low to even start thinking about replacing plugs and wires. Reason why I still want to do it is I was told if you wait anywhere near 10 years, good luck in getting them out. Additionally, I already bought new OEM ACDelco plugs and wires. I'm figuring this will be the first and last time.

 

While you may not want to remove the plugs with the engine hot, you do want to remove the drivers side fuel rail cover. It is more pliable when it is hot.

 

Going to give you the short version. The plugs are fine, and at most will have a light red tint to the electrodes from additives in the fuel only.

On the spark plug wires, they are fine as well, and if they have problems the car with either the plugs or wires, would be throwing codes.

So the way I see this ending, your will end up destroying the wires when trying to remove them/end up have to replace them; all so you can just pull the plugs to look at them and put them right back in.

So if you want something to do on the car, take the plugs and wires back to get a refund, and just pull the MAF to clean it with spray cleaner, and change the air filters out with new filters (cabin filter and air intake filter).

 

I don't recall anything being all that in the way on the passenger side rear. I know there are some AC and/or heater lines over that way but they aren't bad.

Having a few different size (short) extensions and a flexible spark plug socket (with built in magnet) always made it fairly painless for me. I can't remember what you actually need for that one specifically, but I know I've changed them in a parking lot during my lunch break.. so it can't be that bad. Gear wrench makes a pretty nice little set of spark plug sockets, with and without extension built in and a flexible curved ratchet for like $50. Well worth the money IMO.

What dano says about the fuel rail covers is right.. I cracked the driver side cover trying to get it off one day when it was cold out. Specifically trying to bend it the right direction so the fuel line would slide through the slot that's cut into it caused it to crack. So, I'd listen to him.

 

There is a black plastic part that comes off near the battery tray that gets in the way. I removed it.

 

Can't help you on the black thingy you're talking about but I do agree to removing plugs long before 100,000 miles as I have heard stories about pulling threads when trying to remove plugs after they have been in the head a long time. I did remove my plugs and wires this summer when I put a Z06 exhaust on my car and I didn't damage the wires or the plugs doing it.

 

My vehicle: 06 LS2.

I changed the plugs without hassle using a plug socket and various combinations of 2" & 4" extensions with a universal. I removed the battery to access plug #8 but did not have any problem with the harness bracket on the frame. Removed the beauty covers years ago and did not have to remove any other parts to access the plugs. For the plug wires, I was sure to grasp both the boot and metal sleeve, make a 1/4 turn twist to ensure the boot was free from the ceramic, then pulled off - fine. Ruined two wires with two mistakes: 1) pulled rubber boot only without twisting to make sure it was loose, which resulted in a wire torn from the plug lead 2) twisted rubber boot only to loosen and not the sleeve as well, which resulted in a torn boot. Had no problem with plug #8 using the twist & pull while holding both the boot and sleeve.

Agree 1000%. I was picking up low frequency miss on the scanner (1 to 3 events per 10000) and decided to investigate only to find: 1) plugs were all fine, 2) I broke two wires when pulling, 3) I really only wasted money and time for peace of mind.

Other experience - I have an F250 5.4L with the dreaded "frozen plugs" at 110K miles (google it) and even that only had one plug frozen requiring some finesse but still did not strip the threads. Be sure to do this when the engine is COLD. I don't see a problem with leaving the plugs in for the 100K recommended by GM.

 

Those Ford plugs are pretty rough if it's the ones I'm thinking of. The super long weird looking ones?

 

we've broken a few in the head. stupid 2 piece design. Champion made a 1 piece design that won't repeat. seems to only happen on triton engines

Back to vettes. I have a deep 5/8 swivel spark plug socket and get them all out without any extentions. I just pulled them out tonight as I dropped my headers to do my clutch. nothing fancy needed. rail covers can come of to give some room though. You wanna twist the wires before you pull. and pull the boot not the wire.

 

I pull the alternator for easy access to #1. I broke a plug there the first time.

 

timd, Please let me know exactly how you removed it on your car. It seems to be of no value, so I'd like to do the same. Thanks

 

I did my 08 base at around 50K miles out of GP (General Principal). Yes, I agree with Dano and others, if the car is running great, the plugs are fine. But I wanted to do it anyway just to "read" them and put some never-seize on them. But there are other things you can do too.

So there was nothing to read. They looked great. I did break a wire and couldn't find a good replacement that day and my car was off the road for a few days in good weather. It gave me a chance to get a set of good wires (Taylor)and keep a few spare OEM wires in back just in case it happens again.

Note, I did it without removing anything or special tools. You have to be somewhat experienced to put some of them back because you are working somewhat blindly, using feel and proper angle. So it might not be that easy if you haven't done a bunch before.

Now here is why I responded: If you DO add some anti-seize to the threads, which I always do, your torque value will change. You can look it up. So, if you torque to factory dry spec, you run a chance of stripping it from the grease reducing the friction. A significant part of the torque comes from the thread friction; the other part from elongation. So just be aware. Maybe there will be no problem with spark plugs in LSx motors, but I did once run into this on a motorcycle head stud and someone explained what I had done by using anti-seize. (with spark plugs I've never used a torque wrench, just get them a little snug with one hand, I don't know, just by feel, I'm sure most people do that too)

 

The alternator Tom? Seriously??? You guys are WAAYYYYYY overthinking this.

I was already planning on checking my plugs last night after the car started up a little funny before one of my passes at the track last week. Just to make it a fair comparison I dug out and installed my fuel rail covers (as I don't usually have them on) before starting the stopwatch on my phone. The end result - I got all 8 plugs removed and reinstalled in under 10 minutes start to finish and I wasn't even hurrying.

No removal of the alternator, no removal of the fuel rail, no removal of the fuel rail cover, no removal of the battery and the only tools needed were a socket wrench, short extension and a spark plug socket - that's it.

 

those are the ones. break easily due to poor design.

 

OK .. I have changed out quite a few wires and plugs... if this is the first time removing the spark plugs, more than likely you will break a wire or two....if you are not using OEM wires ( overpriced IMO ) .. make sure you buy 10mm or better -- ( I used Taylor 10.2mm wires ) .. most auto part stock 8mm wires and this may cause intermittent misfires or fry from the heat. The plastic covers are easy to remove and I have yet to crack one -- and is necessary to swap out plug wires... just make sure you make sure the wires are correct seated --- otherwise they will eventually vibrate loose.


the only tool I used was a socket with an extension to remove the spark plugs. all are accessible