How in the HELL....
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 23,124
Likes: 117
From: San Antonio Texas
How in the HELL....
do you get plugs 6&8 changed in an LT1 or LT4? Any tricks I might be unaware of? I know I did it once when I was younger and more tolerant than the grumpy impatient bastard I am now. The dipstick is right in the way and I think it must be welded in there. Can't for the life of me remember how I got my hands in there last time. I MUST be much larger now than I was 3 Opti's ago! It fowled the plugs this time and the ones I got out so far need changing anyway. I might be able to pop the wire off #6 from underneath with a long screwdriver because I can see the edge of it over the cat & starter, but......
The fun to
ratio has gone past the tipping point!
The fun to
ratio has gone past the tipping point!
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I've had luck with a spark-plug socket (The type you can put a wrench on) and open end wrench and of coarse some blood and sweat!! You can also remove the inner wheel well panels.
Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
As I recall on my 95 LT1, the easiest time I had (especially w/ #8) was to access it from underneath the car. I also read that removing the AC housing was one way to access the #8 from above, but I never tried that.
As for the sparkplug socket with a wrench hex top, that too has done the trick several times for me as well.
(Just ONE of the advantages to the LT5 is getting to the friggin spark plugs...NO PROBLEM!)
As for the sparkplug socket with a wrench hex top, that too has done the trick several times for me as well.
(Just ONE of the advantages to the LT5 is getting to the friggin spark plugs...NO PROBLEM!)
Burning Brakes
Joined: Jun 2014
Posts: 1,020
Likes: 51
From: Connecticut
The easiest way is to remove the inner fender well pieces and tire. Then use an extension, a universal joint extension and spark plug socket to remove and replace those two plugs. The same is true for the opposite side.
The fastest way is to use a regular deep well socket and good, slender ratchet and a lot of flowery words.
The fastest way is to use a regular deep well socket and good, slender ratchet and a lot of flowery words.
Last edited by kg4fku; Aug 6, 2015 at 12:00 PM.
Team Owner
Joined: Sep 2003
Posts: 25,363
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As I recall on my 95 LT1, the easiest time I had (especially w/ #8) was to access it from underneath the car. I also read that removing the AC housing was one way to access the #8 from above, but I never tried that.
As for the sparkplug socket with a wrench hex top, that too has done the trick several times for me as well.
(Just ONE of the advantages to the LT5 is getting to the friggin spark plugs...NO PROBLEM!)
As for the sparkplug socket with a wrench hex top, that too has done the trick several times for me as well.
(Just ONE of the advantages to the LT5 is getting to the friggin spark plugs...NO PROBLEM!)
On the LT1 I believe the wheel-house panel removal would certainly be a first move.
A V8 Monza was a challenge for sure. It's been a very long while but I believe I recall a fellow that used a 'hole-saw' and cap-plugs the first time.
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 23,124
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From: San Antonio Texas
Well, I got tired of screwing around trying to go around stuff. I pulled off that air pipe that goes from the back of the manifold to the exhaust manifold. That was an adventure in itself. Then removed those pesky little wire loom holders and it really opened up the area. Plugs are now all out. Next rodeo is getting that stiff hose for the compression tester in there!
Just got 4 holes checked so far and it got too hot in the garage to do any more today.Those checked OK. Hoping I didn't wash out the rings when the Opti went bad. I was out in the desert, no cell service, so I had to crip it back to civilization where I could call a trailer. It went through a tank of gas in 100 miles.
It was pig rich and stinking of gas when I shut it down.
Just got 4 holes checked so far and it got too hot in the garage to do any more today.Those checked OK. Hoping I didn't wash out the rings when the Opti went bad. I was out in the desert, no cell service, so I had to crip it back to civilization where I could call a trailer. It went through a tank of gas in 100 miles. It was pig rich and stinking of gas when I shut it down.
Melting Slicks
Joined: Jul 2008
Posts: 2,268
Likes: 142
From: Ottawa Ontario
Hoping I didn't wash out the rings when the Opti went bad. I was out in the desert, no cell service, so I had to crip it back to civilization where I could call a trailer. It went through a tank of gas in 100 miles. It was pig rich and stinking of gas when I shut it down.
It was pig rich and stinking of gas when I shut it down.
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Thread Starter
Team Owner
Joined: Feb 2006
Posts: 23,124
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From: San Antonio Texas
That's what I've been thinking too, but I had my scanner in the car with me when all this went down and I plugged it in while driving back to civilization. The only codes I got were random and multiple misfires from opti. No other codes showed up. Plugs were pretty sooty and the exhaust tips were black and stinky. We'll see when I get it all back together. I'm hoping I didn't ruin it. Don't think I can afford a rebuild right now.