inconsistant idle, possible TB leak? Tune?

[AlexSza]

Hi, ive been having very strange idle problems the past few weeks, almost months and i cant seem to place my finger on it. As i start the car, idles high yada yada Fiav works well and idles down when up to temperature.

If i unplug the ISC it will idle super low and almost die, but when turning head lamps, blower fan, or even brake lights, it will bog my engine down and cause a surge. It isnt consistant though. Somedays it will idle fine at 1k now because adjusting the idle screw with all my lights on so it doesnt go down to 500 and bounce around and die on me at stop lights.

The intake system is tight and sealed from the filter to the throttle body, I do run a FMIC. its a problem im starting to think it may be a tuning issue because of how heavy i have the engine set with the cams that are in it.

It has ran well in the past, after replacing the clutch cylinder on the transmission THAT is when i noticed the change, also after driving the car, shutting it off then starting it again, it will spike idle to about 2k+ then drop, sometimes it wont drop.

Need all possible opinions on what i may have here, i have the time and space to rip apart anything on the car if need be, on the weekends haha.

thanks

 

[JBDdsmer610]

u might say everything is tight but did u do a boost leak test you could have a leake in other places besides the intake system vac lines ect....

 

[clipser-gs-t]

You gotta start with a boost leak test.

 

[92AWDHX40]

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

could be lots of things start here with the idle issues.

 

[AlexSza]

Completed a boost leak over the weekend and found the couplers were getting loose, it's all air tight sealed now. Still idles like dog shit and now forced to drive it to work making people think I want to race at each stop light

 

[Burntz]

Just another easy test you can do.. have your alternator load checked at a local parts store. My car was acting a little screwy, had a bad alternator. Injectors depend on alt output to a certain extent. Never hurts to rule it out.

Also, if you have ECM Link, make sure you do the TPS adjustment. If not, make sure you measure the resistance on the TPS and ensure its properly set. Those things are SO picky.