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sic86
11th May 2010, 12:04 AM
hi all

just a quick question about cold start, on my TB all the vacuum lines have been blocked off including the cold start and the coolant lines. What is the best of getting the motor to fire up without using the throttle.

slide86
11th May 2010, 12:10 AM
the key is my best bet

the cold start injector is on the manifold, if its hooked up and you have the idle screw set sorta correct you will get the car to start.

just set the idle screw so the engine idles at 900rpm all the time and it will be fine

sic86
11th May 2010, 12:25 AM
thanks for the info the cold start injector is connected. when fire it up from cold i need about 3 mins with foot on throttle before it idles.

Hen may possibly be a nut
11th May 2010, 12:41 AM
Either connect water lines to the idle valve thing in your throttle body, or just up the idle speed using the adjuster screw (you'll have to balance between cold idling and a too-high hot idle speed).

Cold start injector (from memory) only runs for a few seconds during a cold start, so should have no effect on idle. It really is only there to help get the engine going in very cold conditions.

Hen

Skylar
11th May 2010, 01:38 AM
Either connect water lines to the idle valve thing in your throttle body, or just up the idle speed using the adjuster screw (you'll have to balance between cold idling and a too-high hot idle speed).
Hen

1200 warm and 700 cold, I think, is what my car does. would prefer warm idle lower but eh, not worth the effort.

ke70dave
11th May 2010, 09:33 AM
Cold start injector (from memory) only runs for a few seconds during a cold start, so should have no effect on idle. It really is only there to help get the engine going in very cold conditions.

Hen

yer my understanding is that the "cold start" is that extra injector that is sorta stuck in the side of the manifold.

there is a temp switch in the back of the head (its brown plug i think) that is in the circuit for that injector, and then when the temperature has warmed up enough the extra injector stops firing.

so the extra injector may be present for the first few minuites of engine runnning, which i think is possible since my engine smells uber rich for the first few minuits of running. then it comes good.

all that water lines crap around your maniflold is the idle up for when its cold (note: different to the cold start). on my engine i just blocked off everything i could, and set the idle using the idle screw and the screw that stops the throttle from closing all the way, as others have stated.

also i belive that the water lines are there to actually warm up the intake manifold/throttle body. apparently in REALLY cold climates (ie sub zero) they have problems with intake temperatures being so low that the air is so cold it just wont mix well with the fuel, (atomisation?) so they need to warm up the intake to help it. apparently also the throttle body can freeze from "wind chill" from the incoming air. i dare say that would never be a problem in australia.

only problem with this is that there is no idle up when its cold, like every other engine has. which is only really a problem on really really cold mornings when it will tend to stall quite easily. my remedy for this is just letting it idle for a bit before i start driving. i usually go and start my car, then lock up the house etc. give it a few minuites to warm up.

so i woudl check that brown plug on the back of your head, and also make sure the inejctor plug is on as well.

having said that you can drive it bone cold, you just have be mindfull that its gonna run rich, and gonna stall easily. but thats only a problem if you are stop/starting. cruising is fine.

to the OP: if you are saying that you need to keep the engine going manually when its cold, i say something is up with your engine, maybe the idle is set way to low, or the cold start injector isnt working how it should.

Richard
11th May 2010, 09:41 AM
must be a comon 4age thing mione does it too

timbo
11th May 2010, 11:45 AM
i blocked off my cold idle up on the throttle body as it didn't work and the car idled at 2100rpm all the time... i just have to keep my foot on the throttle for a few seconds to get motor going on first start up, no big issue and dave, i do the exact same thing with locking the house up haha