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Discussion Starter #1
Just cleaned the phenolic spacers and egr valve on my 93 sts because of some rough running.
Put it all back together started her up...revs up to 4000rpm without me touching the pedal. Removed air intake from throttle body...started engine again, still reving very high and butterfly on throttle body is closed.
Can anyone help with this....because kind of wishing I had not touched it at the moment
 

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You need to adjust the ISC...... Its normal, assuming things were pretty dirty.....

Did you at some point in time have to adjust the idle because it was too low.....
 

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Discussion Starter #3
elwesso said:
You need to adjust the ISC...... Its normal, assuming things were pretty dirty.....

Did you at some point in time have to adjust the idle because it was too low.....

Hi elwesso

Don,t wish to seem thick but what is the ISC and how do you ajust it
And no I have never touched the idle

thanx
 

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Well, I dont think you need to adjust the IAC, but you do need to do the relearn procedure...... Since you have not messed with the adjustment screws.....

Do a search for IAC or ISC.....
 

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Discussion Starter #5
elwesso said:
Well, I dont think you need to adjust the IAC, but you do need to do the relearn procedure...... Since you have not messed with the adjustment screws.....

Do a search for IAC or ISC.....
Would removing and replacing the top engine cover held in by 12 bolts screw anything up...does this have to be air tight ?
 

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No..... Its just a plastic cover for looks and to somewhat protect the wires and hoses underneath it.......
 

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Discussion Starter #7
elwesso said:
No..... Its just a plastic cover for looks and to somewhat protect the wires and hoses underneath it.......
Can anyone tell me the relearn proceadure the only one I have found says to let the engine idle for 13 mins

Sorry not going to have it idle at 13mins at 4000rpm on driveway and watch it self distruct

Any help is appriciated
 

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I'm not 100% sure if this is the correct procedure for this car. This works for 97 deville.
To perform the TP Sensor Learn:
1.Turn the ignition switch to the ON position, with the engine not
running.
2.Wait for 30 seconds.
3.Turn the ignition switch to the Lock position.
Wait for 30 seconds.
4. Start car.
 

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The intake cover on your 1993 Northstar is functional.(Later models have 4 bolts and are a cosmetic cover) If it is not tight you have a vacuum leak and that could be the cause of your high idle. I would recheck the gasket and bolts.
 

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Dutch said:
The intake cover on your 1993 Northstar is functional.(Later models have 4 bolts and are a cosmetic cover) If it is not tight you have a vacuum leak and that could be the cause of your high idle. I would recheck the gasket and bolts.
I stand corrected..... :eek:

In my experience, a vacuum leak usually causes a lower than normal idle.......
 

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Im not doing too well today, am I...... :D

Point taken..... :)
 

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STS2NV said:
Can anyone tell me the relearn proceadure the only one I have found says to let the engine idle for 13 mins

Sorry not going to have it idle at 13mins at 4000rpm on driveway and watch it self distruct

Any help is appriciated

ISC = Idle Solenoid Control

As DUTCH noted the top cover is functional on the 93' and 94' Northstar engine, and must be completely sealed. An air leak at this point will in effect be like having the throttle plate partially open.

Check the cover screws for tightness, but do not over tighten. This cover is sealed by a gasket that has a silicone bead, over tightening will not help.

You removed the intake to clean the spacers;

Did you remember to reconnect the vacuum line to the power brake unit?

Are all of the small vacuum lines hooked up? (Check again)

Did you carefully clean or replace the intake seals? Made sure that they all set properly in their grooves?

Did you have any trouble placing the intake back on, as in accidentally knocking the intake seal(s) from their grooves?

With the engine off and air cleaner and tube removed; look at the throttle plate, it should look like it is completely closed. If not the throttle cable may not be correctly inserted and will not let the throttle plate close properly.
 

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Re: Idle Learn Procedure

Great info!!!!
 

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Discussion Starter #16
growe3 said:
ISC = Idle Solenoid Control

As DUTCH noted the top cover is functional on the 93' and 94' Northstar engine, and must be completely sealed. An air leak at this point will in effect be like having the throttle plate partially open.

Check the cover screws for tightness, but do not over tighten. This cover is sealed by a gasket that has a silicone bead, over tightening will not help.

You removed the intake to clean the spacers;

Did you remember to reconnect the vacuum line to the power brake unit?

Are all of the small vacuum lines hooked up? (Check again)

Did you carefully clean or replace the intake seals? Made sure that they all set properly in their grooves?

Did you have any trouble placing the intake back on, as in accidentally knocking the intake seal(s) from their grooves?

With the engine off and air cleaner and tube removed; look at the throttle plate, it should look like it is completely closed. If not the throttle cable may not be correctly inserted and will not let the throttle plate close properly.

Thank you Dutch

I had not fully tightened the top cover....duh.
All is well now.
Thank you everyone for your help


93 STS
Pearl White
2002 Rims
208,000miles
 
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