TPS ground has 5 volts

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oogah

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Map sensor checks out so back to square 1 I guess, for the hell of it I tested voltage and resistance to iac pins and have no power on either and a resistance of .04 on bottom ( orientation when plugged in ) and a whole 15.24 on the top wire

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oogah

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I can't find anything and I've checked all over the motor, if there is a vacuum leak then I've completely missed, but I am concerned about the iac wires
 
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oogah

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I've tried checking everything involved with those two but right now I just can't seem to find the reason why
 

JKP

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You can pull up the throttle % as you press it down with the engine off, ignition on.

Also, you can turn the ignition on and read the MAP sensor. The reading with the engine off should be the ambient pressure. You can get the ambient pressure from most cell phones and GPS units. Or you can take the local weather reading and correct for your locations altitude. You subtract .1 in Hg per 100 feet above sea level as the weather reading is corrected to sea level.
 
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oogah

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By percent do you mean I can see the percentage the computer says the throttles open, and I'm so confused about the ambient pressure, so I can read what the computer says it is and set it to the correct number, does it come up as Hg
 

JKP

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It's a relative percentage, but yes. On mine, it goes from 15% to about 75% IIRC. So 15% is closed, 75 is wide open. This is because the throttle doesn't use a full rotation of the sensor. The computer learns the closed and WOT positions. So, I can watch it go from 15 to 75 to verify it's smooth.

When you turn the key on, the pcm takes a measurement from the MAP before the engine starts. This lets the PCM know the air density where you are. It then uses this value until you restart the Jeep or floor it. This reading is the ambient air pressure where you are.

You can check your MAP's accuracy by turning the key to on and note the pressure then compare to your ambient at your location.

On my scanner it reads in inches of Hg.

Once you start the engine, the MAP sensor should read somewhere in the vicinity of 18 in Hg less than the ambient at idle.

If you get your pressure from the local weather, just subtract 0.1 in Hg per 100 ft of altitude.
 

JKP

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Also, you can't set the MAP, if it's off, it's bad and needs to be replaced.

Recenty mine was reading the pressure that corresponded to around 1000 ft elevation and I'm at about 300 ft. So, it was causing a slightly lean condition.
 
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oogah

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Just wanted to make sure it wasn't something as simple as that, I'm just running out of Ideas for what it could be