Idle -Why another thread...so many
Thread Starter
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
So, you are not disconnecting the IAC at all....just getting the engine warm to go into closed loop and then turning the adjusting screw on the TB and checking the count.
Yes, timing is correct. I took off the IAC off the TB this weekend. All passages are clean...like new aluminum and pintle is set at 1-1/8"(just a hair less) and checked the resistance on the IAC electrical....all in specification.
This is a completely different way of setting the idle than "by the book", but with the real time data count this might do it. Always looking at different approaches. Thanks -John
Yes, timing is correct. I took off the IAC off the TB this weekend. All passages are clean...like new aluminum and pintle is set at 1-1/8"(just a hair less) and checked the resistance on the IAC electrical....all in specification.
This is a completely different way of setting the idle than "by the book", but with the real time data count this might do it. Always looking at different approaches. Thanks -John
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
So, you are not disconnecting the IAC at all....just getting the engine warm to go into closed loop and then turning the adjusting screw on the TB and checking the count.
Yes, timing is correct. I took off the IAC off the TB this weekend. All passages are clean...like new aluminum and pintle is set at 1-1/8"(just a hair less) and checked the resistance on the IAC electrical....all in specification.
This is a completely different way of setting the idle than "by the book", but with the real time data count this might do it. Always looking at different approaches. Thanks -John
Yes, timing is correct. I took off the IAC off the TB this weekend. All passages are clean...like new aluminum and pintle is set at 1-1/8"(just a hair less) and checked the resistance on the IAC electrical....all in specification.
This is a completely different way of setting the idle than "by the book", but with the real time data count this might do it. Always looking at different approaches. Thanks -John
Did you take the IAC housing off and clean it too?
This is a method taught to me by Brian Ebert of Hightechmotorsport. So far, it has worked on my 74219 cam with the Superram and my new cam.
Thread Starter
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
aklim,
IAC housing was perfectly clean when I pulled it off last weekend. Not any sign of carbon or any other deposits. Pulled the IAC out and tested the resistance and checked the distance on the pintle. All passages good.
I will try your method soon.....105 out side currently and just finished up 12+ hr day. I will wait until it is cooler.....WINTER
Thanks for your help.
-John
IAC housing was perfectly clean when I pulled it off last weekend. Not any sign of carbon or any other deposits. Pulled the IAC out and tested the resistance and checked the distance on the pintle. All passages good.
I will try your method soon.....105 out side currently and just finished up 12+ hr day. I will wait until it is cooler.....WINTER
Thanks for your help.
-John
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
aklim,
IAC housing was perfectly clean when I pulled it off last weekend. Not any sign of carbon or any other deposits. Pulled the IAC out and tested the resistance and checked the distance on the pintle. All passages good.
I will try your method soon.....105 out side currently and just finished up 12+ hr day. I will wait until it is cooler.....WINTER
Thanks for your help.
-John
IAC housing was perfectly clean when I pulled it off last weekend. Not any sign of carbon or any other deposits. Pulled the IAC out and tested the resistance and checked the distance on the pintle. All passages good.
I will try your method soon.....105 out side currently and just finished up 12+ hr day. I will wait until it is cooler.....WINTER
Thanks for your help.
-John
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
Crank up the idle to get steady rpms (it has to be steady). Spray some starter fluid ALL around the intake, and wait for increased revs. EVERYWHERE that vacuum gets routed, you have to check. Like a water hose in reverse - every fork in the hose can have its own leak downstream. Same with vacuum.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Crank up the idle to get steady rpms (it has to be steady). Spray some starter fluid ALL around the intake, and wait for increased revs. EVERYWHERE that vacuum gets routed, you have to check. Like a water hose in reverse - every fork in the hose can have its own leak downstream. Same with vacuum.
Thread Starter
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
I used a "C" clamp to close off the brake booster vacuum line....no change. I used a vacuum gauge hooked into a "T" fitting and connected to every vacuum line that was running off the plenum and other sources...all showed 15 inches of vacuum...except the small line to the air diverters which showed 8 inches. These valves send air to the exhaust manifold or to the cat. I sprayed carb cleaner around intake and all runners on the SR to the degree that I had cleaner RUNNING off the back of the block.....NO change in rpms. When in open look, idle is fairly steady, once in closed loop it swings. I just don't see a vacuum leak anywhere.
I am taking off for a few days to spend with the kids and grandchildren, will tackle this upon return. I am thinking that aklim's suggested adjustment might do the trick. Will let you know.
I am taking off for a few days to spend with the kids and grandchildren, will tackle this upon return. I am thinking that aklim's suggested adjustment might do the trick. Will let you know.
Last edited by John A. Marker; Jul 9, 2008 at 08:00 PM.
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Team Owner
Joined: Jul 2004
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From: Hartford WI
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I thought that the AIR valve is a one way to the exhaust manifold and the air pump feeds the diverter valve which is governed electrically? At least that was how it was done on my 91 Firebird and when I transplanted the motor, I took it all off.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I must admit that you are right from the diagram. It has been so many years since mine "fell off" that I must have forgotten. Either that or since 93 when I had my superram on, I must have forgotten to put in the vacuum. Guess we learn something everyday or have someone knock back what we forgot.