Off Roading Forums banner

Vac leaks...

879 views 6 replies 2 participants last post by  Steve83 
G
#1 ·
Man, everything has been going great.....
1) Now, today I get in drive off and notice the selector for my AC panel is not working (only blowing through defrost)?
2) While getting gas I checked the oil and noticed a constant "SSSHHHHHHH" on the right side kinda by the "black canister?" Pulled out my trusty 1/4 inch hose and searched to come up with nothing? Are these related?

As of now, I've used carb spray and 1/4 inch hose to seach for vac leaks any other tricks?
Thanks,CMG

1989 bronco...100 and something thousand miles...351...C6
 
#2 ·
Yes, they're related. Odds are the vacuum motor right next to the passenger hood hinge is bad. It selects fresh or recirculated air, but with it leaking, there's not enough vacuum to operate the other motors. Take the vac line off of it and plug it. The hissing should stop and the selector should work again. I have a few I've collected from junkyards so I don't know if the dealer or parts stores sell them.

Steve
83 Custom w/95 4.9L EFI, 78 NP435, 83 NP208, 83 D44IFS 3.07, 87 Ford 8.8ABS 3.08, Michelin LTX AT 31x10.50R15
 
G
#4 ·
Well, I checked where you said to and I did have a crack, so I replaced and ac/heat is working!

Now, my hissing is still there, however I've gotten closer to where I think it might be? Kinda by the TPS, Alternator and Throttle Body. Sounds like its right in there somewhere. I think it might just be the Throttle Body?
Thanks for the help!

1989 bronco...100 and something thousand miles...351...C6
 
#5 ·
In that area, could definitely be a leaking EGR valve or the line that goes into it. Check memory for EGR related codes. Or your throttle body gasket might have a leak and you're hearing an air intake leak. And there is a vac line going into the throttle body, to that air bypass valve. Good luck and glad to hear that it's working again.

It's a Jeep thing? My Bronco thing will run over your little Jeep thing.

Muddybronco
 
G
#6 ·
Thanks for the insight. Looks like I'm gonna be back outside for a while.

Curious, since the hissing is very loud I should be able to locate it with a hose, however I've gone all over that area and its produced nothing?

1989 bronco...100 and something thousand miles...351...C6
 
#7 ·
The throttle hisses at idle. It's normal. Raise it to 2K rpm for a moment and see if it disappears. But you shouldn't be able to hear it unless you have a FIPK or other free-breathing filter. Check the hoses from the throttle to the air filter box.

Steve
83 Custom w/95 4.9L EFI, 78 NP435, 83 NP208, 83 D44IFS 3.07, 87 Ford 8.8ABS 3.08, Michelin LTX AT 31x10.50R15
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top