Idel adj
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Joined: Dec 2007
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From: Yardville NJ
Idel adj
Hay guys trying to set Idel on my 86 do what it,s say,s in book and here, but nothing seams to happen. I have the adj. screw backed allmost all the way out dose not tuch the lanage and idel still wont come down to less 6 rpm in gear. any help ???????
Burning Brakes
Joined: Jun 2008
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From: New Smyrna Beach Florida
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From: So. Cal.
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Maybe squit some throttle body cleaner in the throttle body while its running. Possibly a dirty TB.
Are there any codes?
Mike
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Joined: Mar 1999
Posts: 678
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From: Oslo, Norway
Hi. The idle shall be adjustedin a specialm way. Do read Lars Grimsrud's description which is taken from the book.
Shortly it is to make sure that the IAC is closed. Thendisconnect the connector to the IAC. Disconnect the ignition cable theat ensure the ignition advance. This connector is as I remember at the near the fire wall and near the brake booster and is blackish in colour. Then start the engine and coax it a bit because the idle is lnormally low. then adjust with the idle screw to about 450 rpm. If the idle is too high there is a vacuum leak which must be repaired. But if you manage to adjust the min idle to about 450 its ok. Then connect the advance connector and start up after connecting the IAC. This is only aproxiamte how its done but read the grimsrud recommendation. I am sure its here in the forum some place. Think its called adjustment of minimum idle air.
It is correct that the idle is controlled by the ECM via the IAC. But before doing any adjustment ensure that the throttlebody is clean from carbon deposites.
If the idle is too high you have to search for vacuum leaks.
Good luck
Shortly it is to make sure that the IAC is closed. Thendisconnect the connector to the IAC. Disconnect the ignition cable theat ensure the ignition advance. This connector is as I remember at the near the fire wall and near the brake booster and is blackish in colour. Then start the engine and coax it a bit because the idle is lnormally low. then adjust with the idle screw to about 450 rpm. If the idle is too high there is a vacuum leak which must be repaired. But if you manage to adjust the min idle to about 450 its ok. Then connect the advance connector and start up after connecting the IAC. This is only aproxiamte how its done but read the grimsrud recommendation. I am sure its here in the forum some place. Think its called adjustment of minimum idle air.
It is correct that the idle is controlled by the ECM via the IAC. But before doing any adjustment ensure that the throttlebody is clean from carbon deposites.
If the idle is too high you have to search for vacuum leaks.
Good luck
Instructor
Joined: Aug 2010
Posts: 119
Likes: 47
From: TX
As in the above post this information was passd to me 2 weeks ago. IF your IAC - TPS and ECM are good this is the way to do it.
http://web.archive.org/web/200402030...D=55&TopicID=2
http://web.archive.org/web/200402030...D=55&TopicID=2
