idle issues with new cam
His car is untuned currently car just got back on the road.
Hey try slight adjustment on set screw going no more than 3% total using your scan tool to monitor real time,then turn key off unplug tps turn key on and verify 0% tps, then key off and reconnect. I'd still try that method but start out slow and remember how much you turn the screw. Should work. Main thing your trying to achieve is more idel air flow since the iac will not be able to keep up. When you get your tune the iac counts will be readjusted then you should be able to return the set screw. You lt1 guys concur for a cammed lt1 even though this is true for my ls1?
Hey try slight adjustment on set screw going no more than 3% total using your scan tool to monitor real time,then turn key off unplug tps turn key on and verify 0% tps, then key off and reconnect. I'd still try that method but start out slow and remember how much you turn the screw. Should work. Main thing your trying to achieve is more idel air flow since the iac will not be able to keep up. When you get your tune the iac counts will be readjusted then you should be able to return the set screw. You lt1 guys concur for a cammed lt1 even though this is true for my ls1?
Might help, but it will always drop down like that when coming to a stop. Coming off throttle is a important part of the tune. Several mail order tunes Ive had will have a slight problem in that area and will take a little work to get it right.
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Joined: Apr 2008
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adjusting the stop screw has negative effects on TPS volts and IAC counts.
after tune the owner "may" also find it necessary to drill/enlarge the IAC hole on TB to resolve possible idle issues. This should not be done without first scanning car to read IAC counts (30-35) and TPS volts (.67vdc closed & 4.5vdc full open). Tuner will assume the TPS & IAC is set right.
