4.6 Get Up And Go!

[StangVert00]

Greetings,
I own a '00 GT 'Vert. (Auto)
Sometimes when I place the car in Reverse, and have my foot on the brake, the engine revs up for a few seconds up like I have tapped the gas pedal. I'm glad my foot is on the brake when this happens!
Any ideas as to what is going on? No "idiot lights" are lit. And it has done this before.

Thanks!

StangVert00

 

[codyGT]

It sounds like the idle air motor is messed up.

 

[007]

It sounds like the idle air motor is messed up.

The what?

 

[bdcardinal]

IAC maybe, (idle air control motor). its the little solenoid looking thing on the side of your throttle body.

 

[007]

IAC maybe, (idle air control motor). its the little solenoid looking thing on the side of your throttle body.

Errr. I thought it was a valve. I didnt know of any motor?

 

[Go HoTO!]

Oh, you guys are killing me! The comments missing from this post are "thingy", "thing a mig gigger", and the "whoozet". (I am just having some fun).

As much as Cody made me chuckle, he is probably correct. The IAC is an electrically operated valve....not a motor. It allows air to bypass the TB when the TB is closed at idle. The IAC opens and closes based on a number of complicated conditions including, but not limited to, ambient conditions and engine load (ie AC being on or off).

The fact that you notice this in reverse, may be completely coincidental. I would say for sure if it were a 5 speed. I really find it hard to believe that the car would know what gear you are in. Does it definately do this when you put it in reverse? Does the condition repeat itself over and over?

Also, does it ONLY ocurr when you defrost is turned on? Try it with the defrost on and off.

 

[StangVert00]

Oh, you guys are killing me! The comments missing from this post are "thingy", "thing a mig gigger", and the "whoozet". (I am just having some fun).

As much as Cody made me chuckle, he is probably correct. The IAC is an electrically operated valve....not a motor. It allows air to bypass the TB when the TB is closed at idle. The IAC opens and closes based on a number of complicated conditions including, but not limited to, ambient conditions and engine load (ie AC being on or off).

The fact that you notice this in reverse, may be completely coincidental. I would say for sure if it were a 5 speed. I really find it hard to believe that the car would know what gear you are in. Does it definately do this when you put it in reverse? Does the condition repeat itself over and over?

Also, does it ONLY ocurr when you defrost is turned on? Try it with the defrost on and off.

To answer your question, yes, I have noticed it only in Reverse.
I don't use the defrost now, but I will take your advice, and try it off and on.

And thanks to all those who commented!

 

[007]

To answer your question, yes, I have noticed it only in Reverse.
I don't use the defrost now, but I will take your advice, and try it off and on.

And thanks to all those who commented!

Is your car an auto. Is it just shifting slow? Revs are always higher in neutral or park than in gear. What if you dont have the brake on, do you go anywhere?

 

[StangVert00]

Is your car an auto. Is it just shifting slow? Revs are always higher in neutral or park than in gear. What if you dont have the brake on, do you go anywhere?

My 'Stang is an Auto.

Here is the sequence of events:

I start the car. It starts normally with no abnormal problems.
I place my foot on the brake and shift it into Reverse.
A few seconds later, the engine revs up by itself for about 2 seconds.
There have been times when I was backing up without the brake and it reved up again, but I quickly put my foot on the brake. But, it only did that once.
The other times, my foot was still on the brake when it reved up.

 

[bowens99GT]

my auto does that too....pisses me off too.