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tpunx99GSX
05-14-2010, 01:31 PM
Ok so i think all three of these are related but i want to ask your opinions.

Idle:
The car idles at 1200-1300 when cold and warming up. very smooth.
Idle Surge:
After the car is fully heated it starts idle surging slowly. Drops to 900 rpms, then climbs very slowly up to 1300 then drops back down to 900. If i push in the clutch it will climb even slower.
Base timing Adjustment:
When i first got the car running and was setting the base timing, i ended up setting it to around 2 degrees BTDC. Mainly because if i set it to 5 or 10 degrees BTDC it would idle surge and idle really high, like around 2000 rpms. Granted this was when the new head gasket was just installed and the motor only had 25 miles on it. Im going to attempt to readjust today.
Heat:
Currently i have no thermostat in. The car warms up and sits right in the middle. but after driving for a bit when i get to the lower speeds it starts to head towards the H and get hot, it never gets past that first line but gets hot enough to make me worry.

My theory on how these are all related:
My belief is that being that the Base timing is set so close to TDC its causing the heat issues, but also with that the thermostat being uninstalled is constantly flowing the coolant through the system and not allowing the coolant to get much time in the radiator to cool down before getting thrown through the system again. And while on the highway it says perfectly in the average range, but this is likely caused by the airflow that is reaching the radiator is cooling the coolant more rapidly.
The Idle surge and Idle i think are related to the base timing as well. but how would i go about adjusting the timing down to 5 deg BTDC without it raising the idle to 2k rpm? Should i maybe try the green cap CAS and see if its maybe a faulty CAS?

What do you all think?

Kracka
05-14-2010, 01:34 PM
Get a thermostat back in there and flush the cooling system; it's very likely the radiator is full of gunk/corrosion/who knows what. Get your base timing set correctly and perform a boost leak test. Once those are good if it still idle surges then you're going to want to look at the throttle body and clean/rebuild if needed.

Halon
05-14-2010, 01:40 PM
You don't adjust your idle by adjusting your base timing. Set your base timing to 5, that's where it's supposed to be. Adjust your idle with the BISS screw. And like Chris said, verify no boost/vacuum leaks as those only enhance idle problems.

tpunx99GSX
05-14-2010, 01:51 PM
I know theres no leaks in the system, i have already performed a boost leak check. It only happens when the system is heated up.
ill try the biss screw. but i think he threw a bolt where the biss screw should be so ill have to see if that works like a regular one. :(

Kracka
05-14-2010, 01:52 PM
...and that didn't raise a red flag as potentially the issue to you? Get the bolt out of there and replace it with a new BISS screw, o-ring, and cap.

Halon
05-14-2010, 01:54 PM
That's gotta be a nice contributor to your idle issues...

And you understand there is a difference between a cold and warm car right? You have a bypass built into your TB (FIAV) that allows extra air in when cold to keep your idle up. Once the car is warm that closes off.

You need to set your idle once it's warm.

tehehodi
05-14-2010, 01:58 PM
He blocked those FIAV lines off.

Kracka
05-14-2010, 01:59 PM
Do you have a coolant run to your TB?

Halon
05-14-2010, 02:00 PM
He blocked those FIAV lines off.

Did he use a block-off platetoo? Or just not hook up the lines?

tehehodi
05-14-2010, 02:01 PM
Plugged the coolant lines that go to the TB. Thats all i know of.