High idle in cold weather

[Jeffrey]

Hello everyone!
I have an 01 hyundai elantra that when the weather gets colder (<40 degrees) that starts with a high idle. It will start and jump up to around ~2000 to 2500 rpm for a few seconds before dying down to normal. A bit nervous about the high idle at startup. Does this sound normal or what?
Cheers and thanks for the replys.

Topic

[dan]

the only things that i know can cause high idle is a stuck open throttle body, a malfunctioning idle air control, and Vacuum leaks…

otherwise your engine is designed in very cold weather too bring RPMs up on initial start up too get the oils flowing and the engine too warm up a little quicker… my engine revs about 1,250-1,500RPM for a little while at start up, then drops down too about 1,000RPM, then when its all warmed up it idles happly between 720-750RPM… but 2,500 sounds a little excessive, has it ever done this before in cold weather? i am guessing your engine is a DOHC 2 liter?

[Bill]

I would say that the high idle speed is normal. That said, those cars had known issues with coolant temp sensors. If it’s reading a lower temp than the coolant really is it could cause a problem. The PCM doesn’t know how cold it is, and it only knows what the sensor is telling it. If it has an air intake temp sensor (which I don’t think it does) the PCM will compare the values and will set a fault code if not close to each other.
You would need a scan tool that reads data to verify that.

[Jeffrey]

Thank you for the replies. Yes it is the 2L and it has done this last winter. It did this today around noon while heading to lunch and the temperature outside was in the 50s. It will high idle for about 10 seconds then settles down to the normal idle.

The dash temperature gauge seems to read normal but I don’t have a scan tool to see what the exact reading is. When i warms up, it goes to the mid point as normal. Error at the low end?

[Jay]

Pretty sure its normal. My car does this. If its warm, it starts to idle (600 rpm’s), cold it starts in a higher idle (1200 rpm’s) and drops down gradually, when real cold it starts at a very high idle (2000 rpm’s) and gradually goes down as the car warms up.

[Bill]

There are 2 temp sensors. One for the gauge and one for the PCM.

[EricTheCarGuy]

I agree with the group that it’s probably normal. I would add however that if someone adjusted the base idle, if it is adjustable, that they may have adjusted it too much and the IAC is not able to compensate for the increased throttle opening.

Keep us posted.

[Author]

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