Missfire When Engine Cold ? Any Ideas

[FENZ]

hey all

been reading up flat out but nothing really sounds like the problem i have

my R33 runs like a bag of crap when its cold the problem started about three days ago when i drove home from work

it cuts in and out i will be driving along and all of a sudden it starts coughing and spluttering then running normal and so on

when the engine gets to normal running temp it stops and runs like a dream again so ANY IDEAS ????

i have had the car about a mounth i have rescently put new aluminium radiator and vacume lines if that might have disrupted something

Edited March 3, 2011 by FENZ

[scotty nm35]

Perhaps the radiator is keeping the ecu in it's cold start map for longer, it just sounds like it's running rich. Have you done the usual? Clean afm, change the plugs etc? You didn't put a low temp thermostat in there did you?

It sounds like the afm wire may be loose too.

[Victory]

When Skylines are cold they go into a "warm up mode" that makes them run extra rich and restricts power so that you do not do any engine damage when they are cold. If you install a large aluminium radiator you only make this situation worse because it will take even longer to get some tempreture into the motor.

As well if you look at your oil pressure you will see that it is high while to oil is cold and only comes down to a normal level when it has warmed up and started to thin out.

The simple solution to this is to not drive the car until you have some movement in the water tempreture gauge and a reduction in oil pressure. If you run an oil cooler it is good to have a thermostat in the line to allow the oil to warm up before it starts running through the cooler.

What I normally do in the morning is to start the car and let it idle while I am getting my stuff together and packed into the car (the deep rumble pisses off the neighbours to no end) and then when it is showing that it is starting to warm up drive off and it works perfectly every time.