1997 Blazer 4.3L, 159k miles, 2 door, lifted 4 inches or so

So I just got a blazer recently and it idled slightly rough. I took off the throttle body to get to the idle air control valve and clean it a bit. It was missing a mounting bolt and so it was not clamped down tight enough and has caused a leak of yellowish bubbly material. I got a new screw, I tried to remount the throttle body, and I find that the old screw is broken and lodged wayyyyy down in there (about 3.5 inches)

I attached pictures to see what the clean socket looks like vs the clogged socket, and to see exactly where I'm talking about if you don't know where the throttle body is.

I plan on driving this blazer only as my winter beater, but taking as best care of it as I can. From my understanding, a throttle body isn't a part that needs to be replaced usually ever. Does anybody know of any ways to securely mount this corner (close left) permanently? My idea was to put LOTS of weight down on the throttle body + gasket and fill the hole with cement and let the cement flow slightly over the corner of the throttle body... probably not a very good idea though! Lol.

Is the entire black case that the throttle body mounts to, replaceable without too intense work? Any ideas are appreciated greatly!

Aw man, Image 2 is upsidedown, image 3 should be rotated 90deg counter clockwise, and image 4 is upsidedown. Sorry!

 

Hello, if that is one of the two front bolts, the front bolts tighten into the lower intake manifold. You would probably need to remove the upper plenum, once removed you can only hope that there is enough sticking out to get a hold on with some pliers. Otherwise, a drill and easy out is the next option.
If you do try this, get a can of Kroil and soak the bolt overnight. Its a seeping oil.
Oh yeah, to check if there would be any part of the bolt sticking out of the lower manifold, measure the height of the plenum and then stick something into the hole and compare the differences.
Good luck!

 

Thank you for the reply! You're right, it is one of the two front bolts. Is the upper plenum also called the upper intake manifold? Because I'm seeing videos on how to do that where you have to take out the air conditioning, coolant lines, fuel lines, and lots of things that look difficult.
If you have 30 seconds, go to this video and pause it at 8:26 Is that the point where I would have to get to!? Quite intimidating for me lol.
If so, I think id try the Kroil soak and an easy out xD

 

Pretty much backyard wrench turner in the video. Use a genuine GM factory shop manual, (check your local library or Ebay) it will show you the correct way to do the job. He removed the plenum and lower intake manifold together. You only need to remove the plenum, and don't have to fool with the distributor, or AC compressor. If you can't remove the broken bolt from the lower intake manifold, check with a boneyard and get a used one from a junk engine, (cheap).

 

Well said. The only reason you'd have to remove lower is if you need to drill and easy out the bolt. Also, if you decide that it needed all the drilling and stuff, and have never done it before, This wouldn't be the part to learn on.
Maybe you'll get lucky and when you remove the upper intake the stud will be sticking up about an inch or so.
Good luck
Later

 

I didn't watch the whole video. That guy is replacing the lower manifold gaskets, so he's taking other stuff off that you have to remove to get the entire lower manifold out (and maybe even thing[s] that don't need to come off at all)

To fix your problem, you really only need to remove the upper plenum.

Whether you want to do the lower manifold gaskets at the same time is up to you. if you see a plastic gasket frame between the metal lower manifold and the head, you should consider doing this as well. There are two kinds of plastic gaskets, those that leak, and those that will leak (usually pretty soon).

If you only need to do the upper, you only need to disconnect/remove these items:

• Fuel lines and electrical connector on the fuel injector assembly
• EVAP hose(s) and electrical connector
• Electrical connectors on the TPS, IAC and MAP sensor
• Throttle body
• Ignition coil

I think that's it. If I missed anything, someone will be along in a bit to flame me about it.

Once you have the upper plenum off, there should bee enough bolt/stud sticking up to work with. Here's some tips about removing the broken bolt piece.

First, heat the stud/bolt piece with a torch until it's red hot. Use MAP gas or Oxy/Acetylene torch. Concentrate the heat on the bolt/stud, not the aluminum of the manifold itself. Once it's cherry red, press a candle to it and let the wax melt into the threaded joint. Turn it with vice grips. Don't break it again, if it won't turn, repeat with heat and wax one more time.

If that doesn't remove the broken bolt piece,find a nut that fits over the broken end of the bolt. Weld the nut to the broken bolt and try to remove it with a wrench.Usually, by this point,the heat cycles, expansion and contraction will break the threads loose.

If it's still seized, it will need to be drilled, tapped and helicoiled, or get a used lower manifold.

Easy-outs don't remove seized broken bolts! Easy-outs break off in seized bolts! If, while you're drilling for the helicoil,the piece starts moving, then, an easy-out will turn it. If you break off a drill bit or easy-out in the thing,you are screwed and you need another manifold.

More to come a little later.

 

Oh wow, great idea/guide! You prefer candle wax over something like PB blaster penetrating oil? I feel like the penetrating oil being specifically engineered for the job would work better. Not trying to be sarcastic, I'm genuinely naiive when it comes to this lol. Welding a nut onto it is a brilliant idea though!

Ill also look into the GM shop manual too if I can find a free PDF version of it. That's a great idea because if I get a bit lost, Ill have that to refer to rather than another backyard wrench turner lol. Ill get started on it after memorial weekend and then let the thread know how it goes!

 

As promised, some additional info.

The plenum gasket is technically reusable. However, as they get older, they tend to get a little crunchy (that's bad). If you don't know for sure that yours are less than three to five years old, you'll want to have a new plenum gasket set available. Fel-Pro MS-95816 is adequate for that. If you want the new metal lower intake gaskets, get only Fel-Pro MS-98000-T, which includes upper plenum gaskets, much better metal lower intake gaskets, and new/improved valve cover gaskets and o-rings.
I usually apply either PB Blaster or my own home-brew penetrant (ATF + acetone, shake well to mix before applying) before the wrench touches the bolt. A broken bolt for me is already beyond those solutions.

The heat from the torch is most important. Squirting PB blaster or whatever on cherry-red hot metal boils off (and often flash burns) the more volatile parts, and smokes the rest with some awful smelling (and likely unhealthy) smoke and vapors. The ash and residue left behind isn't very slippery. Candle wax might ignite with a gentle flame, but the melted wax is liquid, slippery and wicks well into the joint. If it hardens, a bit more heat from the torch gets it flowing again.

Check your public library. They usually have access to factory service info online. It's for DIY and non-commercial use, and often access restricted to the computers in the library only, or sometimes if you carry your own laptop or tablet in and use their WiFi, that works.

People talk down Chiltons, but my Chiltons had better info for dealing with the upper plenum in the section about removing/replacing the fuel injector assembly than I got from the factory service manual (online) at the dealership.

 

I took the plenum off and the bolt descends about a millimeter past the intake manifold :/ I guess I will have to try an easy out. After all, I cant make it much worse. Thanks for all of your help everyone!