Vacuum Leak on Throttle Body

Super6XJ

New member
Well.. i Have pin pointed the Vacuum Leak.. and it is on my throttle Body..

I have pointed out in the Pictures Below.. that it is the 2nd hole.. down that Hisses While the Engine is on..
Now What i have done...
I have Changed the IAC.. But didn't seem to change anything..
I have covered the opening With Electrical Tape.. so it wont Hiss or anything like that.. (didn't Help Either)

Well.. what i wanted to ask was.. Is there something sapose to be in that hole?
If not.. what is making This Vacuum Leak?
Or do i have to get a New Throttle Body..

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My Engine is 97 Wrangler I-6 ,4.0

any Help is Appreciated.. 8)
 

There are supposed to be two vacuum lines in that plug that run toward the front of the intake then towards the driver's fender. Don't recall what they're for. Plug them both good if you don't need 'em.
 
well i have my laptop right next to my jeep in my Garage, i'm going to try to find any hanging Lines.. and gonna try getting to the bottom of this..
Thank you for your Reply.. 8)

EDIT:
I Found The Right Line for That hole. I just didn't see it casue it was with all the wires..
Well It is Running 100% Better!! Thank You...
So now i just have to Chane a Fuel injector.. (easy)

I am sooooo Relived That , that was it..
thanks for the Help!
 
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hello, the other day i was just doing some looking around on my TJ and i found an open vacuum port on my intake right below the throttle body. when the engine is running and i plug the port with my finger the engine bogs way down then returns to normal same when i let go. so i cut a peice of my windsheild wiper fluid line put a screw in it and plugged the port for now but im still concernd that it may be something important. any ideas? thx
 

hello, the other day i was just doing some looking around on my TJ and i found an open vacuum port on my intake right below the throttle body. when the engine is running and i plug the port with my finger the engine bogs way down then returns to normal same when i let go. so i cut a peice of my windsheild wiper fluid line put a screw in it and plugged the port for now but im still concernd that it may be something important. any ideas? thx
Look around the area where the vacuum port is for a dangling vacuum line. If you cant find one, take a pic of which port and post it here so we can help you figure out what goes there.
 
The hole that leaks (vacuum), is the port for the vacuum line for the MAP sensor. If your MAP isn't hooked up, in all likelihood, the motor runs very poorly and tends to run way rich, if at all, without stalling.
One of those holes is blind and doesn't go completely through, the other that goes all the way through and has vacuum, seriously needs a vacuum line running from it to the MAP sensor. There is usually a pre-formed hard plastic line running from that port to the MAP and connected with a short piece of rubber tubing to the bottom of the MAP sensor.
You can replace the whole line with rubber tubing, but it should be thick walled or fairly stiff so it doesn't collapse under vacuum. You can also buy small party packs (assortments) of plastic fittings, normally used for the windshield washer tubing for end piece couplings/adaptors if need be.

Here is a link identifying most of the sensors and there location, though some of the pictures show a setup with a non stock, modified intake.

http://www.lunghd.com/Tech_Articles/Engine/Basic_Sensors_Diagnostics.htm
 
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hey guys, i have cleaned my battery cables, reset the computer (ECU). and took this picture of the vacuum hoses going into my intake below the trottle body the hose going in at the top left is coming from the brake booster, not sure what its called, the hose on the bottom left is coming from the valve cover, the hose coming fron the bottom right is coming from that black box that i guess is something with the gas tank that captures the fumes? And the top right port that i have plugged up with windsheild wiper hose and a screw is whats missing. any ideas? :???:
 

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Some models have that nipple plugged with a vacuum plug. Some has the emmision line for the purge solenoid. There should also be another line that goes to the firewall with a T connector to the reservoir going under the battery tray and the other inside the cab.
 
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