2 mysterious holes on intake manifold

[shelikesit]

Can't seem to find them in a picture anywhere.<br /><br />On the intake manifold of a 1990 4.3L directly under the automatic choke side of the carburetor there are 2 holes that go into the intake.<br /><br />Anyone know what these are for and should they be plugged or should something be going to them.<br /><br />Thank you.......

 

[Laddies]

Re: 2 mysterious holes on intake manifold

It sounds like holes for a heat tube for a auto/choke for a differant carb yours is probable heated electricly, don't worry about it

 

[javsam]

Re: 2 mysterious holes on intake manifold

I too have the two holes on my 89 4.3 intake, one has the choke pull off attached to it, and the other was just an open hole. I plugged it because it was sucking just air.. and if yours is also open ,I would suggest plugging yours. you dont want to burn a valve from too much air.<br />javsam

 

[DHPMARINE]

Re: 2 mysterious holes on intake manifold

One hole is for the heat tube that warms (and opens ) the choke.The other hole should be open,to allow the air to get to the heat tube.<br /><br />DHP

 

[shelikesit]

Re: 2 mysterious holes on intake manifold

Thanks DHP and all for the input.<br /><br />I guess I have what is an electric choke so neither of those holes are routed anywhere.<br /><br />Should one be going to the carb somewhere and the other plugged? <br /><br />Or plug them both?<br /><br />Thank You.

 

[DHPMARINE]

Re: 2 mysterious holes on intake manifold

Whoops.I got the years mixed up.1989 had the heat tube,1990 DID have the electric choke.I would think you could leave the holes alone,or plug them.It won't make a difference.And won't cause a vacuum problem,the passage between them runs thru the coolant section,not the actual intake part.<br /><br />DHP

 

[shelikesit]

Re: 2 mysterious holes on intake manifold

I was wondering why they didn't try to suck my fingertips through when I covered them.<br /><br />It seemed like nothing at all was happening.<br /><br />Thanks again.

 

[DHPMARINE]

Re: 2 mysterious holes on intake manifold

The carb does the sucking thru the tube.The holes in the manifold are only a passageway to get warm air into the choke.<br /><br />DHP

 

[Reel Poor]

Re: 2 mysterious holes on intake manifold

Originally posted by javsam:<br /> I too have the two holes on my 89 4.3 intake, one has the choke pull off attached to it, and the other was just an open hole. I plugged it because it was sucking just air.. and if yours is also open ,I would suggest plugging yours. you dont want to burn a valve from too much air.<br />javsam

Not trying to hijack a thread here but.....<br /><br />javsam if you blocked that hole off on your engine you are causing a problem with the choke system<br /><br />

posted December 25, 2005 08:52 AM<br /> One hole is for the heat tube that warms (and opens ) the choke.The other hole should be open,to allow the air to get to the heat tube.<br /><br />DHP

posted December 25, 2005 10:00 AM<br /> The carb does the sucking thru the tube.The holes in the manifold are only a passageway to get warm air into the choke.<br /><br />DHP

 

[javsam]

Re: 2 mysterious holes on intake manifold

o.k, thanks for the info.<br />javsam