# Cold Start Idle Too High



## nelam (Feb 16, 2005)

Hi All,

My '89 Sentra w/GA16i has a very high idle speed after a cold start. I did some research on this issue and cleaned out the coolant line that goes into and out of the dashpot unit. The unit was not plugged, and looks relatively clean. The thermostat is working properly.

What other components should I check for? I assume an air pocket in that unit might cause the this problem. Is there an unique way to bleed the coolant system on GA16i? I read thru the Haynes manual, and it doesn't tell me much about this engine. I guess it was only in production for 2 yrs.

The engine runs great, but the cold idle is a concern to me since it puts alot of wear and tear to a cold engine.

Thanks,
Nelson


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## SuperSentra4203 (Dec 17, 2002)

Define high idle. All 4 cylinders I have ever owned ran a cold idle of about 1700-2500rpm. If your high idle continues after the car is warmed up, then you need to replace the thingy (I cant remember the name) at the throttle body. Two coolant lines run to it, it is esentially a wax-packed servo that controls idle speed depending on temp. I think what you already described was this. Cleanig them out doenst always work, I cleaned mine and it did the same, so I just kept driving it the way it was, car had 165K of the most abused miles before it was totalled out, and the engine still ran strong. If you do have a air pocket in the cooling system, you'll know right away. "Smoke" will come outta the radiator at the cap, and you'll have no heat.


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## dreamteam (Jul 29, 2005)

Hello and welcome to the forum.

Yes the engine was only inproduction for two years.
Don't hold that fact aganst it .
It's still a pretty good motor.

You will need to check that IIAC valve.
its an idle control valve located at the base of the throttle body.
around back and tward the passenger side.

It looks like a small cylinder with a two prong plug on it. (two wires)
There are two screws holding it in.
When you remove it, be very carefull not to loose the spring.
Clean it with electronic cleaner or some weak carb cleaner.
Re-assemble and place the spring .

Now on to the cooling system.
There is an air bleed screw located just below the 
plastic wire loom for the spark plugs.
You will see two bolts, it is the second one down.
use a 10 mm to loosen it.(engine cold, not running)
open the radiator and pour in coolant until it runs out of the loosened bolt 
close it up and your done.


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