For those of you with the TBI injection...

...I am working on a unique project with two TBs, and I need to delete one of the two IAC motors. To do this, I need to buy or make a plug, but I haven't been able to verify what the thread type and size is.

I assume since everything else is metric that it would be too, but I don't know how to be sure since I can't measure that big with 100% accuracy.

Does anyone happen to know what the thread type and size is, of the IAC motor port?

Thanks.

 

I think cgi had a plug you could use. Just use a thread pitch gauge to see if its standard to metric and vernier calipers to measure the outside. If you are plucking the passage just tap were the pentle goes with nap and use a plug.

 

Can't just tap that inner plug since I am linking two different IAC chambers with a tube. I need the chamber itself to be sealed at both the outer port for the IAC motor and the pentle port.

I don't have easy access to the tools I would need to measure. Hence asking. Given more time I could measure myself, but I would like to get this plug ordered this weekend.

Thanks.

 

why not parallel wire the 2 TBs and set minimum air so the IACs run in an acceptable range @ idle

2 TBs, 2 alternators... uh oh!!

 

Not sure what your trying to do but it looks like 7/8-16

 

I'll check on that, thanks. Honestly I'd be shocked it if were really SAE.

I took the IAC motor to a local hardware store earlier today and nothing in SAE or Metric fit. It almost threaded into an M20 but the the thread count was wrong.

 

You might be able to rethread the tb and use a orb an 10 it that helps. Im not sure were my thread pitch gauge is for metric but standard 16 fit perfect. the outside of the threads measured .875

 

I'll try again at the local hardware store, and will compare to a 7/8"-16 and see where that goes. I didn't try the bolts, just the nuts.

 

I think its a odd ball one unf is 14 threads per inch and unc for 7/8 is 9.

 

Yeah you're not kidding. Called the hardware store with no luck. I tried quite a few internet searches and while I may have found a lead or two it's not something that'll be common. In fact I'm thinking ordering one is a crap shoot, and if I can get a local machinist to help make one that'll be easier.

 

Just gut an old IAC and weld it up.

 

https://www.thirdgen.org/forums/tbi/...-both-tbs.html

https://www.thirdgen.org/forums/tbi/...tbis-dual.html

 

Why not just extend the pintle all the way out and then leave the old IACV in . That should work at least until you find another option.
(look down inside the TBI where you can see the pintle head to ensure its closed all the way.)

 

I made a ball from silicone glue once and just trimmed a bit when dry and stuffed in hole until I replaced IAC. My crossfire had two IAC's and one died. I still had functionality just 50% less. Maybe it ran better that way? LOL

 

That's actually really close to what I am trying to do. When I was searching for solutions to my issues, I came across those same threads on different forums and saved the images. I'm using those images as best as I can to solve some of the problems and a few things I am doing differently.

Simpson and I have emailed back a few times about the projects, and while he gave me a lot of good advice, mostly he implied his past work with Crossfire TBs has soured his taste for them and he has no interest in spending any time trying to remember the problems of solutions.

Update - I think I finally found the plug I need to do it right and it's on it's way. I'll know in a day or so and I will post an update.

I did like the idea of extending the pintle but my TBs are closer together than the ones from the images in that link, and there isn't enough room for the IAC to be in the bore. It needs to be removed and plugged.

 

One last suggestion if yours dose not work could be using one of the rubber plugs they sell in the hardware/pull out drawers in most hardware stores. They come in many different sizes and the right one should actually thread into the hole.

 

Thanks, I'll add that to my list of backup plans. I have a few floating around in my head. Heck I even contacted a shop I know of that has a 3D printer and the capability to make the plug from a dense plastic. That was an expensive option, but cool.

 

So when you remove the IACV you have two holes your dealing with in order to get it to seal. The large one the actual motor sets in and the breather hole that the pintle seals when closed. That's why I first suggested the IACV with the pintle extended to solve the problem. The rubber plugs would need to be placed one large and one small at either end to solve the problem. Correct ?

 

Yep, I plan to tap it and use an NPT plug. That'll seal the two ports needed to be sealed for the linking of the two chambers to work.

 

I have to admit my way was "hooky" at best and absolutely "jury rigged.(the plugs)"That's not usually the way I roll.
Your way is definitely the way to go.