I live in michigan and we have already had a few mornings in the low 20's and high teens and when i start my car in those cold temps it idles very hard (almost seems like its going to stall) for the first 2 minutes or so. Its an '02 x-type 2.5L. have any ideas what might be causing this? thanks for the help guys!

 

same here.

 

Crowlader, I would first start with a can of throttlebody cleaner (NOT!!!! carb cleaner) and a can of MAF sensor cleaner. Remove the 2 bolts holding the MAF sensor in place and use the MAF cleaner to clean the sensor. Squirt some down the hole (not directly down) and then fill up the hole to let it set for a minute or so. Then dump it out, squirt a little more down there and then reinstall. Then remove the intake from the front of the throttlebody. Then using one finger, hold the butterfly valve open and if you see brown, squirt it with the throttlebody cleaner. Keep spraying till all the brown is gone. Make sure to get the edge of the butterfly valve (big silver disk in the center) as this is known to get build up on it and cause the throttle to stick. Also, look for a small hole on the close side of the throttle body and spray some of the cleaner down the hole. Reinstall everything.

Once you do this, depending on how much throttle body cleaner you used, the car may be hard to start (you have effectively flooded the car). Put the gas pedal to the floor and the start the car. This will prevent the fuel injectors from adding more gas and once the motor starts to fire and attempt to run, take your foot off of the gas except to help get the motor up to speed. You may also get a check engine light. Do not worry. Sometimes this will come in. After a few more trips with the car, the light will clear itself.

 

thanks thermo! I'll get at it this weekend!

 

Sounds like a good idea. I haven't tried that yet. I was going to replace the air intake manifold gaskets next along with spark plugs. i have replaced the o rings on those 2 black plastic valve cylinders on the air intake manifold. that got rid of a slight vacuum leak i was hearing but didnt change the rough idle cold start at 40 degrees f. I can't tell if its getting too much air or not enough air.

but im gonna try this first before replacing gasket and plugs.

 

mobile, i just replaced my gaskets and plugs about a month ago and im still having the issue. So im assuming it wont help. Hopefully what Thermo suggested will do the trick.

 

Well I cleaned out the throttle body and MAFS. It did improve a little but wasn't the primary cause of problem. shouldn't there be a warm up idle speed. My cae idles around 650 when warm and a rough idle around 950 when cooold. Does that sound about right. The computer tries to compensate in really cold temperature and recovers to normal idle speed only after almost shutting off.

Back to the drawing board for me.

 

MObile, my car initially is up around 1,200 RPM and then over time comes down to around 700RPM. So, sounds like your high idle is a little low. Now, what would cause that, not sure. All I can think of is that your engine coolant sensor is reading a little wrong and at low temps, it is not giving an accurate measure of the temp, therefore the computer thinks the motor is warmer than it really is. Without putting the car on a computer, it would be difficult for me to say much beyond that. Do you have a code reader? If not, look into the "ELM 327" and use it with a smart phone. The ELM unit costs about $10 on e-bay and you can download a free app for Android phones that is free (find the Torque app). From there, you can select the engine coolant temp readings and after letting the car sit all night, the indication on the phone should be very close to what outside temp is. But ,that will help you diagnose things.