L98 idle set procedure?
Pro
Joined: Jul 1999
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From: Eagle IDAHO
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Re: L98 idle set procedure? (scorp508)
Considering the heat, it's no wonder.
Key off
jumper A-B ALDL
key on 30 sec
disconnect IAC (key still on)
key off
pull jumper from ALDL
start up
adjust idle stop screw to ~500 rpm
key off
reconnect IAC
done
Tom
Key off
jumper A-B ALDL
key on 30 sec
disconnect IAC (key still on)
key off
pull jumper from ALDL
start up
adjust idle stop screw to ~500 rpm
key off
reconnect IAC
done
Tom
Thread Starter
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: L98 idle set procedure? (NHVett)
Thanks, Tom, I'm not even sure if my car will run at 500 RPM though with this cam. :D Its supposed to have a 900 RPM idle. I guess we'll try anyways. Thanks!
Thread Starter
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: L98 idle set procedure? (scorp508)
Ok that worked great, thanks. :) After adjusting the screw to get a 950 idle I redid the TPS also since it got bumped up to 0.72 at idle. Now I just have to burn a chip to match the 950 because the IAC is parked at 0 now becuase the ECM wants an 800 idle.
Pro
Joined: Jul 1999
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From: Eagle IDAHO
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Re: L98 idle set procedure? (Ray Quayle)
Hi Ray, Got to Scotland June 19th rained on me the whole time. Bedbugs in Hostel. Not a good trip. Wife moved out two days ago to search for greener grass. Not a great summer so far. Now my Vette is blowing oil smoke and has a pronounced miss when tipping the throttle in at low rpms. Ain't life grand :)
Scorp, My cam/spec idle is ~750 as well. Sorry, forgot about resetting the TPS.
Tom
[Modified by NHVett, 4:19 PM 7/6/2003]
Scorp, My cam/spec idle is ~750 as well. Sorry, forgot about resetting the TPS.
Tom
[Modified by NHVett, 4:19 PM 7/6/2003]
Le Mans Master
Joined: May 2003
Posts: 5,203
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From: Las Vegas Nevada
Re: L98 idle set procedure? (NHVett)
:grouphug: At least you still have the vette. :nopity
Wife leaving or losing the vette. Which saves the most money. Do we need a poll?
Seriously, sorry to hear that.
[Modified by Southern Comfort, 1:33 PM 7/6/2003]
Wife leaving or losing the vette. Which saves the most money. Do we need a poll?
Seriously, sorry to hear that.
[Modified by Southern Comfort, 1:33 PM 7/6/2003]
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Pro
Joined: Jul 1999
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From: Eagle IDAHO
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Re: L98 idle set procedure? (Southern Comfort)
I've got the Vette, the three Yellow Labs, the house, and she is giving me a monthly check to help w/the mortgage. And, since I don't work in the summer and only two days a week in the fall, winter and spring, I'm smiling.
Let the party begin :party:
[Modified by NHVett, 4:43 PM 7/6/2003]
[Modified by NHVett, 4:43 PM 7/6/2003]
Let the party begin :party:
[Modified by NHVett, 4:43 PM 7/6/2003]
[Modified by NHVett, 4:43 PM 7/6/2003]
- 1986 Original Owner -
Joined: Apr 1999
Posts: 3,193
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From: North Yorkshire, England
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Re: L98 idle set procedure? (NHVett)
Tom,
Sorry I missed your IM. Feel free to e-mail anytime. Address is in sig.
Sorry I missed your IM. Feel free to e-mail anytime. Address is in sig.
Instructor
Joined: Jul 2002
Posts: 121
Likes: 0
From: Quincy Ma
Re: L98 idle set procedure?
The 87 GM Service Manual says to do it this way .. Have things changed since then???? Haynes Manual goes along with NHVET ...
Key off
Jump A-B ALDL
Ignition on at least 30 sec
Disconnect IAC (key still on)
"IMPORTANT" Disconnect the distributor set-timing connector
Start Engine and allow to go to "Closed Loop"
Remove jumper A-B ALDL
Adjust to 450 rpm in neutral for manual or auto
Turn ignition off and reconnect IAC and distributor set-timing connector
Adjust TPS
John
[Modified by John Steen, 6:28 PM 7/11/2003]
Key off
Jump A-B ALDL
Ignition on at least 30 sec
Disconnect IAC (key still on)
"IMPORTANT" Disconnect the distributor set-timing connector
Start Engine and allow to go to "Closed Loop"
Remove jumper A-B ALDL
Adjust to 450 rpm in neutral for manual or auto
Turn ignition off and reconnect IAC and distributor set-timing connector
Adjust TPS
John
[Modified by John Steen, 6:28 PM 7/11/2003]
Melting Slicks
Joined: Apr 2002
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From: St. Charles, MO Route 66 Corvette Club
Re: L98 idle set procedure? (John Steen)
I have to agree with John S in that the distributor connector MUST be disconnected before the idle adjustment procedure. My 89 Helms manual also states to disconnect the connector. Some guy named Lars G. wrote a procedure that is located in the tech section. I tried his method (did not break the connection) and I had a mess! I followed the Helms procedure and she purrs like a kitten. I have learned to set the TPS at about .65 volts (spec is .54 volts) to see improved idle and throttle response. Regards, Sam
