[d_stang_j]

have a 95 gt 5.0 that seems to have a sticky throttle? when i come to a stop in neutral (is a 5 speed) car idles around 2000-2500 rpms and as soon as i tap the gas pedal it drop down to normal idle....??? its driving me nuts, especially when the people in the car next to me start looking at me funny when my cars revving around 2500 rpm, could this be a bad tps

[Wiked]

Or IAC

[d_stang_j]

Originally Posted by Wiked

Or IAC

i know it doesn't mean it couldn't be bad but it less than six months old, so i hoping thats not it

[Wiked]

Try cleaning out the EGR Solenoid, I had to replace that on my car to keep it from lunging, and thats what you might be trying to explain.

[d_stang_j]

Originally Posted by Wiked

Try cleaning out the EGR Solenoid, I had to replace that on my car to keep it from lunging, and thats what you might be trying to explain.

ill look at it but i replaced it when i replaced the IAC

[thatdavidkid]

why not test the sensors first

[seco]

Originally Posted by thatdavidkid

why not test the sensors first

so how do you go about manually testing the sensor?

[thunderchicken]

Check to see the reference values of you throttle position sensor,or you may also have a dirty Idle Air Control motor......

[96greengt]

vacuum leak ?? intake area, plenum area???

[d_stang_j]

will check what i can on the sensors tomorrow, ill have to look you some numbers, unless someone knows the values i should be looking for, thought about a vacuum leak but cant seem to find one, but trust me ill keep looking

[96greengt]

Well, if that pic in your avatar is your engine, I'd look at the rear of the upper intake for any cracked or loose lines (brake cleaner helps you find vacuum leaks too).
As far as values for sensors, they change with certain conditions. TPS volatge at idle should be about .7-.9 volts, wot will be close to 4.8 volts.
Then you have MAF, IAC, TP, PCM, and wiring.

But in no way does any of the emissions have any effect on idle quality unless you have a short in VREF to any given sensor since they all share a common wire and signal.

I just do not see an EGR or EVR for that matter causing an idle concern.

[thunderchicken]

To check for a vacuum leak,you could take a spray of throttle body cleaner and spray all around the area's of the intake,and listen for engine idle changes.....the idle should drop if you find a leak with the spray.....if you have one.....

[thatdavidkid]

Originally Posted by thunderchicken

To check for a vacuum leak,you could take a spray of throttle body cleaner and spray all around the area's of the intake,and listen for engine idle changes.....the idle should drop if you find a leak with the spray.....if you have one.....

or if you have access to a labscope you can backprobe your o2 sensors, you'll be able to more acurately find a leak that way if that is the case

[d_stang_j]

checked all over visual and with starting fluid and couldn't find anything, so now i guess ill start with the sensors, is there anyway of testing the iac valve, looked through alldata but didn't give any info

[d_stang_j]

TPS seems to be good reads .8 and wot reads 4.66, anyone know how to test an IAC valve or motor