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Timing Adjustments - Need Help

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Old Mar 17, 2009 | 12:46 PM
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Default Timing Adjustments - Need Help

Seems like if i set my timing around 6/8 BTDC than it will accelerate no problem, but the idle after warming up is a bit up and down. Now if i turn the distributor clockwise it lowers my timing, get a nice idle, but when i "punch" the gas i get a little hesitation, which just drives me nuts. Any suggestions????
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Old Mar 17, 2009 | 12:48 PM
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It's a 1990 Coupe
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Old Mar 17, 2009 | 12:49 PM
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Set the timing to the right spot, then you might try cleaning your IAC valve.
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Old Mar 17, 2009 | 11:04 PM
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remember to disconnect the tan line / black cable before adjusting it !
then connect it again.-
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Old Mar 18, 2009 | 07:58 AM
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Originally Posted by Corvette505
Seems like if i set my timing around 6/8 BTDC than it will accelerate no problem, but the idle after warming up is a bit up and down. Now if i turn the distributor clockwise it lowers my timing, get a nice idle, but when i "punch" the gas i get a little hesitation, which just drives me nuts. Any suggestions????
Set your timing at 8 and find your idle problem.
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Old Mar 18, 2009 | 09:55 AM
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Originally Posted by Calderone
remember to disconnect the tan line / black cable before adjusting it !
then connect it again.-
BINGO. If the ESC is not disabled base timing will not be correct.
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Old Mar 18, 2009 | 10:01 AM
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Base timing has to be 8 ? i forgot it
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Old Mar 18, 2009 | 10:21 AM
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You have posted this in both General & Tech it's easier to follow if in just one section. A idle that is hunting & timing are 2 different issues. Set base timing, then deal with the idle condition. If you search on here you will find having a dirty IAC & Throttle Body is one of the # 1 cause’s of a hunting idle condition. Cleaning usually takes care of this, you might also want to set your throttle position sensor should be between .42 & .62 volts
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Old Mar 18, 2009 | 03:38 PM
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Originally Posted by Calderone
Base timing has to be 8 ? i forgot it
6 is factory I believe for most but 8 works and give a little better response. Some have done 10 but I remember reading that they had detonation issues.
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Old Mar 18, 2009 | 03:48 PM
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Originally Posted by Iroc57
6 is factory I believe for most but 8 works and give a little better response. Some have done 10 but I remember reading that they had detonation issues.
10 sounds
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Old Mar 19, 2009 | 01:02 AM
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ok, i will try setting it back to 6/8 and dealing with the IAC, TPS, etc

Thanks all
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Old Mar 22, 2009 | 09:39 PM
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what happened ?
did you solve it ?
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Old Mar 22, 2009 | 11:41 PM
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reset my timing, put in a new iac, still have idle issue.....tested the fuel injectors The injectors had many different readings, one was as low a 2.3, others were as high as 17. Funny thing was, when i pulled the elec connector off the bad ones, the idle adjusted just fine. Does this mean the injector truly is bad and I should replace them (i'm not one to replace just one, if im going to do it i'd rather replace them all so they are all consistent with how new they are and same brand etc) or does that mean the problem lies elsewhere?
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