Dec 16, 2014, 12:29 PM
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Spark Plug Change for GS300
Thread Starter
Intermediate
Joined: Mar 2001
Posts: 419
Likes: 14
From: Mississippi
Spark Plug Change for GS300
I just changed the plugs on my '99 GS300 yesterday and I took some pictures of the install. It only took an hour and 45 minutes from start to finish and this was my first time doing it. Don't let anyone tell you that it is too hard and you should let the dealer do it. You will only need basic hand tools. I will post the write up with pictures tomorrow if you guys will make this thread a sticky.
P.S. I also changed the transmission fluid if you want to see a write up of it also.
P.S. I also changed the transmission fluid if you want to see a write up of it also.
Thread Starter
Intermediate
Joined: Mar 2001
Posts: 419
Likes: 14
From: Mississippi
I changed my original plugs (NKG) at 73,000 miles and I noticed a lot of pick up in the lower RPM range. I also cleaned my throttle body and changed my transmission fluid, so these may have helped a bit. I used Denso Irridium plugs that I got from the dealer. Most people say that you have to completely remove the throttle body, but I didn't want to remove the fuel line so I removed all of the other connections and slid it forward so that I could access the plugs. I will resize the pics when I get home tonight. Look for details tomorrow.
Originally posted by redjeeper
I changed my original plugs (NKG) at 73,000 miles and I noticed a lot of pick up in the lower RPM range. I also cleaned my throttle body and changed my transmission fluid, so these may have helped a bit. I used Denso Irridium plugs that I got from the dealer. Most people say that you have to completely remove the throttle body, but I didn't want to remove the fuel line so I removed all of the other connections and slid it forward so that I could access the plugs. I will resize the pics when I get home tonight. Look for details tomorrow.
I changed my original plugs (NKG) at 73,000 miles and I noticed a lot of pick up in the lower RPM range. I also cleaned my throttle body and changed my transmission fluid, so these may have helped a bit. I used Denso Irridium plugs that I got from the dealer. Most people say that you have to completely remove the throttle body, but I didn't want to remove the fuel line so I removed all of the other connections and slid it forward so that I could access the plugs. I will resize the pics when I get home tonight. Look for details tomorrow.
yes please post some pics cause my 99 is due for some plugs and wires
Thread Starter
Intermediate
Joined: Mar 2001
Posts: 419
Likes: 14
From: Mississippi
To change your plugs you will only need basic hand tools such as a socket wrench and some extensions and a set of allen wrenches. It would help to have a swivel extension for your socket wrench as well because the last plug is in an awkward position.
Enjoys the pictures.
Enjoys the pictures.
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Thread Starter
Intermediate
Joined: Mar 2001
Posts: 419
Likes: 14
From: Mississippi
Look under the front of the throttle body and you will see five more screws. Three of them will hold the throttle body and two will hold a bracket under it. Remove all of them. As a side note, the bolt that is in the center of this picture needs to be screwed all of the way out or you will not be able to slide the throttle body out of the way. Trust me, this will save you some time and headaches.
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Thread Starter
Intermediate
Joined: Mar 2001
Posts: 419
Likes: 14
From: Mississippi
In this picture, you see that the throttle body has been slid forward so you can see the plug wires and the coil packs. The little gold screw on the left of the picture will need to be removed in order to get the coil pack out. By the way, coil pack that is directly under the throttle body was a b@$#$ to remove and put back in place. I probaly wasted 15 minutes on this one alone. Once you replace all of the plugs, just put everything back the way you took it out.
The whole job took about an hour and 45 minutes from start to finish. This was my first time doing and this is yet another job that Lexus can't overcharge me for. I hope this writeup helps everyone who has been wanting to do do job but was afriad of the labor involved. Let me know if you have any questions.
The whole job took about an hour and 45 minutes from start to finish. This was my first time doing and this is yet another job that Lexus can't overcharge me for. I hope this writeup helps everyone who has been wanting to do do job but was afriad of the labor involved. Let me know if you have any questions.
Joined: Jul 2002
Posts: 9,859
Likes: 12
From: Waipahu, Waikele, HI
Nice writeup...thanks bro.
Btw...how many miles you got on your GS? I thought the Denso Iridium plugs suppose to last a while....are you swapping for a reason?
Btw...how many miles you got on your GS? I thought the Denso Iridium plugs suppose to last a while....are you swapping for a reason?
nice write up, BUT...
red, thats one VERY nice write up, i could have used it about 6 months ago when i replaced my plugs... BUT, its about time u cleaned that damn engine!!! 
my $0.02.
my $0.02.