Dec 16, 2014, 12:29 PM
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- Lexus IS GS: How to Replace Spark Plugs
Step by step instructions for do-it-yourself repairs
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DIY sparkplugs GS400*******************
Pole Position
Joined: Sep 2003
Posts: 390
Likes: 0
From: Canada
I just changed my plugs about two weeks ago. It was a bit tricky but not that bad. theres the two bolts and then you discconnect the hoses.(in the red circles. and loosen the clamp on the intake tube thingy. (tecnical term) I then just gently twisted it on the big intake tube thingy back and forth till it came off. Just watch to make sure nothing is hung up on it.
Pole Position
Joined: Sep 2003
Posts: 390
Likes: 0
From: Canada
EMFJR, I was in the midst of replying when I got an email notification of your reply. Thanks for your efforts, they're greatly appreciated. I'm going to tackle this tomorrow, I'm watching the Leafs tonight. (Y)
After searching under "engine cover" I found a nice post by e-man here:
https://www.clublexus.com/forums/sho...php?t=224751#8
CL is great, isn't it?
After searching under "engine cover" I found a nice post by e-man here:
https://www.clublexus.com/forums/sho...php?t=224751#8
(2) Once the engine cover is off, you need to take off the black box immediately to the left of the engine (as you're looking at it). The air intake tube coming out of the filter box and going into the throttle body is attached to and a part of this black box. First, take a screwdriver and loosen the clamps holding the air intake to the filter box and to the throttle body. Second, remove the 2 bolts that are holding the black box to the engine (one is in the back and the other is on the left side). Third, remove the 3 vacuum tubes that are attached to the black box. The vacuum tubes are attached to the box with pressure clips. Just squeeze the clips and pull off the rubber tubes. Lastly, remove the air intake tube from both the filter box and the throttle body. The air intake tube is accordian-like where it attaches to the filter box, so it comes off pretty easily. I had to apply a little force to remove the air intake tube from the throttle body.
Pole Position
Joined: Sep 2003
Posts: 390
Likes: 0
From: Canada
I did the job last night. I thought I would throw in a couple of personal thoughts. I'm comfortable fooling around with the car, but I had never changed spark plugs before, although I watched my pops do it a few times growing up. It's a simple job, if you can change your oil you can do it - with the right tools.
I required a flex ratchet, two sized extensions (4" and 10"?), 10 mm socket, and a 5/8" socket and/or a 5/8" spark plug socket. I used both.
I had a hard time taking off the pipe on the throttle body. I don't know if this was appropriate, but I used lithium grease to help get it off. I cleaned it off well afterwards. I cleaned the TB with an oxygen sensor safe carb cleaner while I had it open.
The passenger side is definitely easier to do due to the space available after removing the black box. I left it for last accordingly. I used two different 5/8" sockets, one for removing, one for installing. The spark plug socket was used to remove the plugs. It had a rubber insert that wrapped over the end of the plug and made sure it came out. I didn't want to use it to put the plugs back in because I feared the socket would come off the extension before the plug. Not really something to be worried about in hindsight. Even if that happened, you could hook it out no problem.
Almost as a result of that little strategy I had my own little screwup that added a good 15-20 mins to the job. I was sliding the plugs into the engine because the socket I was using to screw them in with didn't hold them. When I got to the passenger side, I slid one in backwards. I removed the battery to confirm that I in fact had done this (doh!). I found an old antenna and got a length of dental floss and made a little loop on an end and cut the slack. I stuffed the loop into the screw-in end of the antenna. I then put the antenna screw-in over the spark plug and spun it around a couple of times and pulled the floss. I fished it out on the second try and boy was I relieved. Other than that bit of stress, everything wrapped up smoothly. EDIT: I found putting the tube back on the TB was easiest by removing the air filter cover, fitting the tube and everything in place and then putting the cover back on.
The car runs just about the same, maybe a hint smoother and more responsive. It was satisfying cleaning the gunk off the TB and seeing the beat up old plugs though.
I required a flex ratchet, two sized extensions (4" and 10"?), 10 mm socket, and a 5/8" socket and/or a 5/8" spark plug socket. I used both.
I had a hard time taking off the pipe on the throttle body. I don't know if this was appropriate, but I used lithium grease to help get it off. I cleaned it off well afterwards. I cleaned the TB with an oxygen sensor safe carb cleaner while I had it open.
The passenger side is definitely easier to do due to the space available after removing the black box. I left it for last accordingly. I used two different 5/8" sockets, one for removing, one for installing. The spark plug socket was used to remove the plugs. It had a rubber insert that wrapped over the end of the plug and made sure it came out. I didn't want to use it to put the plugs back in because I feared the socket would come off the extension before the plug. Not really something to be worried about in hindsight. Even if that happened, you could hook it out no problem.
Almost as a result of that little strategy I had my own little screwup that added a good 15-20 mins to the job. I was sliding the plugs into the engine because the socket I was using to screw them in with didn't hold them. When I got to the passenger side, I slid one in backwards. I removed the battery to confirm that I in fact had done this (doh!). I found an old antenna and got a length of dental floss and made a little loop on an end and cut the slack. I stuffed the loop into the screw-in end of the antenna. I then put the antenna screw-in over the spark plug and spun it around a couple of times and pulled the floss. I fished it out on the second try and boy was I relieved. Other than that bit of stress, everything wrapped up smoothly. EDIT: I found putting the tube back on the TB was easiest by removing the air filter cover, fitting the tube and everything in place and then putting the cover back on.
The car runs just about the same, maybe a hint smoother and more responsive. It was satisfying cleaning the gunk off the TB and seeing the beat up old plugs though.
