Removing 85 plenum and runner
Thread Starter
Instructor
Joined: Apr 2013
Posts: 229
Likes: 2
Removing 85 plenum and runner
I need to replace my egr temp switch cable.The previous owner removed the runners to put new injectors in it and when he tightend the passenger side runner down the cable was under it.I think this is why it failed.What all needs to be took off to remove the plenum and the passenger side runner?
Drifting
Joined: Aug 2013
Posts: 1,463
Likes: 0
From: Everett Washington
theres 5 bolts on the top and 5 on the bottom if i remember correctly simple torx bit to remove all the screws, and get the top ones on the diriver side and itll pop right out. pick up some gaskets before you tackle it though.
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
It is also good to have several size extensions, 6" being the most helpful to get at everything. There re two bolts that have to be accessed from the opposite side so when you think you have all of them, look on the inside for that last one.
Thread Starter
Instructor
Joined: Apr 2013
Posts: 229
Likes: 2
So unbolt the top runner bolts,the bolts from the plenum to the throttle body,the throttle cable bracket,the line going to the back of the plenum,pull the plenum out,then remove the 4 accessible bolts on the outside of the runner,then the 2 on the inside,and that's it?Am I missing anything?
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
There is only one bolt from the rear in to each runner ( 5 from the front as shown )
The red line shows location of the "hidden " bolt accessed from rear
Usually the bottom runner bolts have to be loose before the plenum will come loose because the runners will clamp the plenum tight.
Depending how long the runner gaskets have been in place, it is not uncommon to have taken all the bolts out
and then need to use a big lever or soft hammer to crack the plenum loose
Last edited by vetteoz; Oct 18, 2013 at 08:12 PM.
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
Yeah thats about it. Remember to not tighten the runners all the way when you put the plenum back on. Make sure you get everything started first before cinching it down. The 4 outside bolts on the top of the runners are canted. They are angled with the surface of the runner so be careful starting them.
Good luck!
Good luck!
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Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
As stated by others, have gaskets handy. No guarantee that you need them but you might...
Now is also a good time to replace the torx bolts with allens.
Another tip is to use anti-seize on the gaskets to prevent them from sticking and having to be scraped off next time. Good time to pull the EGR and clean those passages as well. A small bottle brush and carb cleaner does the trick.
I like doing runner bolts with 1/4" sockets and extensions. The smaller extensions fit past all the things in the way easier than the 3/8 drive.
Now is also a good time to replace the torx bolts with allens.
Another tip is to use anti-seize on the gaskets to prevent them from sticking and having to be scraped off next time. Good time to pull the EGR and clean those passages as well. A small bottle brush and carb cleaner does the trick.
I like doing runner bolts with 1/4" sockets and extensions. The smaller extensions fit past all the things in the way easier than the 3/8 drive.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
Figured wrong
If the gaskets have been in place for any time they bond solid to the runners/plenum meaning that as I noted above ,
even with ALL the runner bolts out, the plenum is still solid and requires some force to break free.
The gaskets are usually destroyed in the process and have to scrapped off the surfaces so new ones can be installed
If the gaskets have been in place for any time they bond solid to the runners/plenum meaning that as I noted above ,
even with ALL the runner bolts out, the plenum is still solid and requires some force to break free.
The gaskets are usually destroyed in the process and have to scrapped off the surfaces so new ones can be installed
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Figured wrong
If the gaskets have been in place for any time they bond solid to the runners/plenum meaning that as I noted above ,
even with ALL the runner bolts out, the plenum is still solid and requires some force to break free.
The gaskets are usually destroyed in the process and have to scrapped off the surfaces so new ones can be installed
If the gaskets have been in place for any time they bond solid to the runners/plenum meaning that as I noted above ,
even with ALL the runner bolts out, the plenum is still solid and requires some force to break free.
The gaskets are usually destroyed in the process and have to scrapped off the surfaces so new ones can be installed
If I was the OP, I would first try to loosen the runner bolts enough to slip the sensor wire out. If the wire insulation is damaged it can be repaired rather than a remove and replace.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
If you read the original post, he stated the previous owner replaced the injectors. So obviously the plenum has been off. It may very well come off easier than you want him to believe.
If I was the OP, I would first try to loosen the runner bolts enough to slip the sensor wire out. If the wire insulation is damaged it can be repaired rather than a remove and replace.
If I was the OP, I would first try to loosen the runner bolts enough to slip the sensor wire out. If the wire insulation is damaged it can be repaired rather than a remove and replace.
Your pretty smart....
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..WW.
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Last edited by WW7; Oct 19, 2013 at 01:56 PM.