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Idle control valve bolt seems to be stripped not sure what to do


I’m removing my idle control valve to clean it. Everything went well until I’m at the last T40 bolt holding it. I go to insert my T40 bolt it doesn’t seem to go in. So I’m like oh I guess it was switched to a smaller T so I put a T30 and it’s to loose so I’m like aww cmon. Here are 2 pictures (not the best I know) of the bolt in question.

Is it actually stripped or it’s some kind of other bolt? I tried a allen but it seems to slip to. If the bolt is stripped, what is my solution? Thanks!

They’re probably not regular Torx bolt heads. But instead Torx-Plus bolt heads.


Hmm. The OEM bolts are Torx so I don’t know.


If a T40 Torx bit is too big, and a T30 Torx bit is too small, and they don’t make a T35 Torx bit, it must be a TP27 Torx bit.


The head of that bolt looks awfully dirty and caked with stuff. Why not squirt it with carb cleaner and scrape it out with a pick or a nail? Couldn’t hurt.

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Sorry I tried again and the T40 goes it ok. It’s just I didn’t fell any resistance or anything since it was stripped but it goes in.

I cleaned it a bit with no success.

I guess I will have to go to a shop and get it out. Hope it’s not expensive.

You can’t help anyone who contradicts what they said in their original post.


So because I went again and verified that I was in fact wrong and my torx goes in, you cannot help me? Ok.


I keep looking at the fasteners and they look like Torx-Plus fasteners.

Read this.

I’ve been repairing vehicles for fifty years.

And I understand when rookies come across a fastener they’ve never seen.

But that separates the pros from the rookies.


That’s not what others are telling me on a E46 forum. They all say the bolt looks stripped and are indeed a T40. I don’t see why all the other bolts would be T40 and this one would have been replaced with a T plus. It makes no sense.

Maybe a stripped T looks like a T plus?

Any chance of using Vice Grip pliers to remove bolts?

If that’s what you believe?

Then go with it?


Someone else mentioned this to me but I don’t quite understand exactly what to do with them. You mean try to turn the head with the grips?

Yes. Stupid to need 10 characters.

Ok I’ll try that tomorrow. I’ve been told they are not torqued a lot so maybe it may work.

Some people love it when they have an excuse to buy some more tools and others will do anything to avoid buying new tools. Or just weld a nut on it but seems simpler to just get a new set of TP bits. May need them again sometime.

Go Cubs. If they don’t win it’s a shame . . .

IMO it looks like it could very well be a Torx plus . . . using a regular Torx socket might remove the bolt, but internally round it, making it that much more difficult to remove the next time

Nevertheless, since it doesn’t seem to budge . . .

Use a 3/8" drive impact driver, in conjunction with a hammer and the appropriate sized socket

I wouldn’t be at all surprised if that will shock the bolt loose, and after that you’ll be able to remove it

BTW . . . why do you want to remove the throttle body entirely, just to clean it

I’ve had good luck cleaning numerous throttle bodies, WITHOUT removing them to clean on the bench

Another thing . . . on several cars out there, you have to use a pro-level scan tool to tell the pcm to relearn the throttle body after such a cleaning. On some cars you’ll get away without doing this. On some others, if you don’t do this, the idle will be erratic, too high, too low, etc. until you perform this step. On yet some others, the idle will be a mess until you drive the vehicle, under various conditions. But others will never “figure it out” on their own

On some of the older Benzes, the throttle body end stops will be relearned every time you turn the ignition to position 2, without starting

I’m not sure if BMW is the same way, though

I just thought I’d warn you of a possible future problem

Pretty sure it’s an OEM bolt.

How do you clean it if you don’t remove it? There’s a little flapping valve in there and to do a proper clean and wipe down I don’t see how I can do that without removing it.

No one mentioned it their DIYs to use some kind of scan tool to reset the idle control valve so should be good.

Don’t know exactly what to say, except I clean most throttle bodies on the engine, without removing them. I’m not unusual, in that respect

Use an old toothbrush, if you feel you can’t get your hand in there. Just an idea

I’m sure it is an OEM bolt, but it might still be a Torx plus. I’m no BMW expert, but I am a professional mechanic, and have run across all sorts of interesting hardware. I’m saying it might be Torx plus, based on the picture you provided. Perhaps if you provided another picture, showing what the bolt looks like, AFTER you cleaned out the crud, which you mentioned having done