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I have a 2005 GT V8 5 speed. I am driving it this winter and the temperature has just started to drop below 0 celsius (32 fehrenheit). When I first start my car it idles at roughly 1400 RPM. It stays that high for over 3 minutes I have not sat there and waited to see how long it takes to drop. Does anyone else's car do this? Is this normal?
 

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mooch said:
I have a 2005 GT V8 5 speed. I am driving it this winter and the temperature has just started to drop below 0 celsius (32 fehrenheit). When I first start my car it idles at roughly 1400 RPM. It stays that high for over 3 minutes I have not sat there and waited to see how long it takes to drop. Does anyone else's car do this? Is this normal?
Mine does that too when it's REALLY cold out. Sometimes I just gas it a little and it goes down. Might go up that high cuz it's trying to warm the engine? Not sure, but you're not the only one.
 

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It's perfectly normal for the engine to idle at a high rpm when first started in cold weather so that the engine does not stall due to higher oil viscosity, which in turn causes higher internal friction from the engine's components, i.e., piston rings, rod and crankshaft bearings, etc.
The computer's coolant and ambient air sensors detect the cold temps, and they feed this data to the computer which in turn signals the fuel injectors' solenoids to pulse more rapidly, and this results in a richer than normal idle fule mixture and a higher than normal idle rpm.

But I'm not sure that the idle speed should remain at 1400 rpm for longer than 3 minutes if the ambient temp is only hovering around 32 F.
The other day my Stang's engine idled at approx. 2000 rpm when it was first fired up with the temp in the teens, but quickly fell back to 1000 rpm within a minute or 2.
 

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ski said:
It's perfectly normal for the engine to idle at a high rpm when first started in cold weather so that the engine does not stall due to higher oil viscosity, which in turn causes higher internal friction from the engine's components, i.e., piston rings, rod and crankshaft bearings, etc.
The computer's coolant and ambient air sensors detect the cold temps, and they feed this data to the computer which in turn signals the fuel injectors' solenoids to pulse more rapidly, and this results in a richer than normal idle fule mixture and a higher than normal idle rpm.

But I'm not sure that the idle speed should remain at 1400 rpm for longer than 3 minutes if the ambient temp is only hovering around 32 F.
The other day my Stang's engine idled at approx. 2000 rpm when it was first fired up with the temp in the teens, but quickly fell back to 1000 rpm within a minute or 2.
My experience also...Dixi backs down to her normal 750 idle within two minutes max on the recent mornings it's been in the high 20s/low 30s here...
 

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I've owned 4 other Ford/Mercury automobiles with the 4.6L engine - they all exhibited the same behavior - high idle (1400-2000 RPM) in cold weather. I complained to Ford years ago when it first happened and they told me it was normal. Indeed, it is...
 

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High rev on cold start

I bought a used '05 V8 GT Convertible mustang, and when I crank in the mornings, no matter what the temp, it revs way up to almost 3,000 rpm for 30 sec. or so and then goes back down to norm, it does whenever the egine has sat for several hours. I think that the previous owner had some reprogramming done too it b/c when you floor it, it shifts very firmly, and I was wondering if it was possible that whoever did it could have screwed up the cold start up or something. I would like to get it back to stock for cold weather, I don't want revving up that much when the motor is cold, especially in cold weather.
 

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I bought a used '05 V8 GT Convertible mustang, and when I crank in the mornings, no matter what the temp, it revs way up to almost 3,000 rpm for 30 sec. or so and then goes back down to norm, it does whenever the egine has sat for several hours. I think that the previous owner had some reprogramming done too it b/c when you floor it, it shifts very firmly, and I was wondering if it was possible that whoever did it could have screwed up the cold start up or something. I would like to get it back to stock for cold weather, I don't want revving up that much when the motor is cold, especially in cold weather.
its normal for it to do this on a cold crank just imagine what mine sounds like with headers, o/r x pipe, and slp lm 1's lol....... its just crazy of how loud it is....... but i do love it ha....
 

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The engine idles high in order to properly heat the O2 sensors and the catalytic converters.
 

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My engine revs around 2,000-2,500 for about 8 seconds. Then goes to 1,500 for another 10 sec then back down to less than 1,000
 

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Mine will go up to 3000 for a few seconds and then go back down, I am worried that this will be bad for it in cold weather, revving so high on a very cold engine, not too mention waking all the neighbors up when I crank it in the mornings.
 

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Mine will go up to 3000 for a few seconds and then go back down, I am worried that this will be bad for it in cold weather, revving so high on a very cold engine, not too mention waking all the neighbors up when I crank it in the mornings.
Do you have a custom tune installed?
 

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I am not sure, I bought the car used from a dealer that didn't know what the previous owner had done to it, but I do know from driving another '05 the mine shifts a lot firmer and at slightly higher rpm, and that there was a new exhaust system put on it
 

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I am not sure, I bought the car used from a dealer that didn't know what the previous owner had done to it, but I do know from driving another '05 the mine shifts a lot firmer and at slightly higher rpm, and that there was a new exhaust system put on it
Sounds like it might have a tune on it already.
 

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My friend has OBD 2 programmer, setting would I look for if I wanted to program it back to factory.
If it's tuned, you would need the original tuner to restore the factory tune. Or take it to Ford and have them reflash it (plan on $100 for this).
 
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