88 Jeep 4x4 automatic 4.0 6 cylinder (TPS)

[Jewel]

Hello,

I have a 1988 Jeep Cherokee automatic 4.0 6 cylinder. I have had now going on forever . . .

I just bought a new throttle position sensor I know there is an adjustment on it though it be slight.

I have been fiddling with it. I need the RPMS to go down. What I cannot figure out is which way to adjust it. If I move the top slightly what does that do and/or if I move the bottom slightly what does that do.

At one point I had the RPMs down enough to be satisfied . . . then I moved it and the RPMs run now about 1200. I would like it to run about 800. Is there anyone that can help me. This is an old problem that I actually fixed at one time, however, I did not write down what I did to fix it.

Peace, Jewel

	Throttle position sensor A throttle position sensor (TPS) is a sensor used to monitor the position of the throttle in an internal combustion engine. The sensor is usually located on the butterfly spindle so that it can directly monitor the position of the butterfly throttle valve. The sensor is usually a potentiometer and therefore provides a variable resistance dependent upon the position of the butterfly valve (and hence throttle position). The sensor signal is used by the Engine Control Unit (ECU) as an input to its control system. The ignition timing and fuel injection timing (and potentially other parameters) are altered depending upon the position of the throttle, and also depending on the rate of change of that position. For example, in fuel injected engines, in order to avoid stalling, extra fuel may be injected if the throttle is opened rapidly (mimicking the accelerator pump of carburetor systems).

[SteelHeadz]

The TPS must be installed so that it can be rotated a few degrees. (If the sensor will not rotate, install the sensor with the throttle shaft on the other side of the socket tangs). The TPS will be under slight tension when rotated. If i remember correctly, counter clockwise will lower the RPM and clockwise increases.

	Throttle position sensor A throttle position sensor (TPS) is a sensor used to monitor the position of the throttle in an internal combustion engine. The sensor is usually located on the butterfly spindle so that it can directly monitor the position of the butterfly throttle valve. The sensor is usually a potentiometer and therefore provides a variable resistance dependent upon the position of the butterfly valve (and hence throttle position). The sensor signal is used by the Engine Control Unit (ECU) as an input to its control system. The ignition timing and fuel injection timing (and potentially other parameters) are altered depending upon the position of the throttle, and also depending on the rate of change of that position. For example, in fuel injected engines, in order to avoid stalling, extra fuel may be injected if the throttle is opened rapidly (mimicking the accelerator pump of carburetor systems).

[Jewel]

Thank you and I am going outside to adjust it.

Peace, Jewel

[Bounty__Hunter]

It should be adjusted using a voltmeter on the TPS outputs or a scan-tool at the diagnostic port.

	Throttle position sensor A throttle position sensor (TPS) is a sensor used to monitor the position of the throttle in an internal combustion engine. The sensor is usually located on the butterfly spindle so that it can directly monitor the position of the butterfly throttle valve. The sensor is usually a potentiometer and therefore provides a variable resistance dependent upon the position of the butterfly valve (and hence throttle position). The sensor signal is used by the Engine Control Unit (ECU) as an input to its control system. The ignition timing and fuel injection timing (and potentially other parameters) are altered depending upon the position of the throttle, and also depending on the rate of change of that position. For example, in fuel injected engines, in order to avoid stalling, extra fuel may be injected if the throttle is opened rapidly (mimicking the accelerator pump of carburetor systems).