Hi Idle
Thread Starter
Racer
Joined: Apr 2007
Posts: 367
Likes: 1
From: Shakopee Minnesota
Hi Idle
I have a 1986 Targa. I originally put a BBK 58mm TB, but took it off due to the extremely high idle that it made my car have. I put the stock TB back on and have driven it for a month or so. Yesterday, I cleaned out the plenum so it is not caked with carbon anymore, and I am idleing about 300-400 RPM's higher than I was before cleaning it. Why am I having issues with a high idle, and how can I bring it down, THe Throttle Linkage on the TB is all the way as flat as it can go. In other words, the screw is basically flat on the TB that adjusts where the linkage fits.
Thanks
Thanks
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
To set min idle (do this first):
Warm up car.
Turn car off. Turn key to "on" position (don't start engine).
Jump terminals A & B in the ALDL with paper clip. Wait 30 seconds.
Disconnect IAC connector. Turn key off. Remove paper clip.
Start up car and adjust min idle to recommended rpms using adjustment screw in TB.
Turn car off. Reconnect IAC connector. Done.
Next, set TPS (throttle position sensor) voltage to .54 volts using voltmeter on top and middle wires (if memory serves) with key in "on" position (engine does not need to be running for this).
Finally, sell 58 mm throttle body and purchase FSM
Warm up car.
Turn car off. Turn key to "on" position (don't start engine).
Jump terminals A & B in the ALDL with paper clip. Wait 30 seconds.
Disconnect IAC connector. Turn key off. Remove paper clip.
Start up car and adjust min idle to recommended rpms using adjustment screw in TB.
Turn car off. Reconnect IAC connector. Done.
Next, set TPS (throttle position sensor) voltage to .54 volts using voltmeter on top and middle wires (if memory serves) with key in "on" position (engine does not need to be running for this).
Finally, sell 58 mm throttle body and purchase FSM
Thread Starter
Racer
Joined: Apr 2007
Posts: 367
Likes: 1
From: Shakopee Minnesota
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
I don't have any pics, but a search might turn up one or two (I remember a recent thread with the ALDL pictured).
I had no issues with the 52 mm BBK TB on my old engine. I was suggesting to sell the 58 mm TB simply because you don't need it; it won't produce any HP gains for a stock or slightly modified engine. On the other hand, a Factory Service Manual would be worth it's weight in gold (or maybe copper - I hear that stuff is worth a lot these days, too
).
I had no issues with the 52 mm BBK TB on my old engine. I was suggesting to sell the 58 mm TB simply because you don't need it; it won't produce any HP gains for a stock or slightly modified engine. On the other hand, a Factory Service Manual would be worth it's weight in gold (or maybe copper - I hear that stuff is worth a lot these days, too
).
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