Anyone ever remove the exhaust manifold?

[jcg-gsx]

So at 38k, my O2 sensor decides to crap out. Long story short, I stripped the O2 sensor bolt trying to get it out, and now need to remove the exhaust manifold to get to it. Once removed, I can decide whether to replace with OE or get headers at that point.

Who has experience removing one of these? Easy, hard, any gotchas? Love to hear from someone who's done it before (more details the better) before I take on this endeavor.

TIA!

 

[Silentnoise713]

So at 38k, my O2 sensor decides to crap out. Long story short, I stripped the O2 sensor bolt trying to get it out, and now need to remove the exhaust manifold to get to it. Once removed, I can decide whether to replace with OE or get headers at that point. Who has experience removing one of these? Easy, hard, any gotchas? Love to hear from someone who's done it before (more details the better) before I take on this endeavor.

TIA!

Call me crazy but shouldn’t you decide if you want aftermarket headers first so you can have the part ready to mount it when you reassemble? Or do you like to do things twice? I suppose you can afford a longer downtime.?.

Before you start taking off the mani, how badly did you round the O2 sensor? You may want to consider using some Kroil or PB Blaster to soak it a bit (I’ve ‘heard’ but have not tried that you can heat the bolt and melt wax into creases) and use an extraction tool like this http://www.sears.com/grip-tite-7-pc-super-sockets-rounded-bolt-remover-metric/p-00934506000P.

If there is space to work with, cut off the end of the O2 sensor and use a 6pt socket that is one size smaller (bet it metric or standard, whichever has the tight fit) and pound it onto the O2 sensor. This should give you good grip to drive it out with a ratchet + breaker bar. You may waste a socket but there are companies that offer lifetime guarantee on said socket

I’ve have not removed the exhaust manifold on this car but have done it with a friend on previous car that was 10 years old and endure a lot of salty winters. With some Kroil pre-treatment, surprisingly most of the bolts came out with the help of a breaker bar but one bolt did break. This is where I learned about helicoil repair kits. Also, I would recommend replacing the exhaust gasket before you reassemble.

My one recommendation is to go into this with no fear. It may require a little muscle but anything that brakes can be fixed (or replace). Just look at the bolts and trace it down and take off components that are in the way to make it easier (easier said than done). It’s not rocket science but take the road of least resistance if it’s an option. Good luck.

 

[jcg-gsx]

Thanks for the info. I plan to try another round of penetrating oil, and an open end wrench, but I'm just looking at worst case scenario. I think headers are just wishful thinking, since I'm from the Repubik of Kalifornia which frowns on such mods!

 

[Silentnoise713]

Thanks for the info. I plan to try another round of penetrating oil, and an open end wrench, but I'm just looking at worst case scenario. I think headers are just wishful thinking, since I'm from the Repubik of Kalifornia which frowns on such mods!

Hmm. Are you using an O2 sensor socket? I would not use an open ended wrech to remove an O2 sensor. You need something that has a solid 6pt mounting surface. You can use a flair nut wrench. This may be the reason why you are stripping the sensor. There's a tool for every job.

 

[jcg-gsx]

Sorry, I meant a closed wrench (6 point). Since the sensor crapped anyways, I'll just cut the wire to slip the wrench over it. I was using an O2 sensor socket (the one with the slit on the side). I knew I shouldn't have forced it, but I thought I felt it giving, then it slipped and that's all she wrote.

 

[flcruising]

You stripped the sensor with a 6 point wrench? 12 point I'd understand, but not 6? You sure it was the right size? Vise-grips are probable the way to go now, can't hurt. Just make sure they have some good teeth.

I've removed exhaust manifolds before, but not on this vehicle. Looks simple enough to access, but you do run the risk of stripping a nut or breaking a stud. If you run the engine and heat up the exhaust, things might remove easier. Same method goes for the O2 sensor.

 

[njaremka]

...I was using an O2 sensor socket (the one with the slit on the side). ...

You stripped the sensor with a 6 point wrench? 12 point I'd understand, but not 6? You sure it was the right size? ...

my guess is the socket wasn't quite seated correctly on the sensor, or it was the wrong size.

...If you run the engine and heat up the exhaust, things might remove easier. Same method goes for the O2 sensor.

i would perform the task with the engine cold. heating it up would cause all the metal parts to expand and get tighter, causing the aluminum head to get soft and be easier to strip. the OP already has a heavy hand for stripping thing out...

 

[jcg-gsx]

Quick Update:

I finally got it off. I had to remove the heat shield, spray the hell out of it with Kano oil and hit it with a torch a couple times. Then slid a 7/8 box wrench over the clip and wire down to the Sensor. With a LOT of coaxing, it finally came loose. The threads were stripped, which was why I was having such a pain of a time! Got the new sensor in, and have driven a couple hundred miles since, no CEL.

Just as a note: 6 point O2 Sockets can and will strip the bolts ( I know this by experience now) because the slit in the socket allows it to flex. With enough pressure, it will flex enough to slip, and then round the bolt.