Gato28d

It runs smooth and great no check engine light and no miss fires. I cant go up a hill no more then 45 M/H and goes only to 3,000 rpm. If i try pushing it more than 3k rpms it shakes and looses power quickly. I was told it might be a back ignition coil? I need help. Thanks!
this only happens when going up hills so pretty much whenever i wanna push it pass 3k rpms

Noah911

Throw a variable or two at it the next time you take the Jeep out for a spin. You said this happens only when driving up a hill on a steep incline, right?

Try this - Get the RPMs up there at slightly above 3000 RPMs on flat land, and while driving down an incline. Keep your Jeep in 1st or 2nd gear to do this.. It will not hurt the Jeep any by keeping the RPMs up steady towards the 3500 RPMs range. They are designed to be able and handle this. I towed my ZJ Jeep Grand Cherokee behind my WJ Jeep Grand Cherokee all of the way from Southern Georgia up to Northern Ohio. I had to climb mountains while doing this too. I probably averaged right at 3250 RPMs throughout the whole trip. In Kentucky, I needed to keep the WJ in 2nd gear maintaining somewhere around 50 - 55 MPH or so, in order to deal with the incline and probably the oxygen level change of elevation when I was climbing the tall mountain over there while passing through the area.

Driving up an incline puts extra load on your Jeep. Check it out and see if this problem is related to the extra load of going up an incline? Or, if it is strictly just an RPM range thing?

Gato28d

I’ve tried putting it in 2nd and after 3k rpms it shakes And still looses power. This didn’t have before. On flat land If i step on it then it does take off quick but again after forcing it pass 3k it does the same thing. Most of the time it doesn’t do it because i dont ever have to push it that far..
but im going to try going down hill in 1st or 2nd gear next time i drive it.

Noah911

It sounds like you should try testing the Throttle Position Sensor (TPS). The TPS has a sweeping voltage from zero throttle input going to full throttle. The voltage sweep will vary from approximately 0.2 Volts at zero throttle input to somewhere around and close to 4.85 VOLTS at maximum throttle input. It should sweep cleanly throughout the range going from 0.2 VOLTS to around 5 VOLTS when testing (no sudden jumps or lags in the voltage readings).

It sounds like maybe the TPS is not giving appropriate higher throttle signals (voltage) to the computer.

Noah911

The TPS is located on the Throttle Body. It is a three-wire sensor. One wire is for ground. Another is for a power supply going to it (a steady 5 VOLTS). And the third wire is for the signal it produces being sent to the PCM for air:fuel management purposes related to your throttle inputs throughout the range. The signal wire should test from 0.2 VOLTS - around 5 VOLTS as you go from minimum to maximum throttle. You can back probe the connection here at the TPS connector to test it. With the ignition key turned to the run position (Jeep engine not running) hook up a voltmeter probe to the TPS connector and go from no throttle to maximum throttle and see what it does?

(edited to add):
If you have to replace the TPS.. It is highly advised to only use another genuine Mopar sensor. The other aftermarket sensors are a lot of times bad right out of the box or fail within months. The Mopar ones are considerably more expensive. But, this is too important of a sensor to risk having another brand aftermarket sensor cause very poor running conditions. Or, fail real soon after installing it to cost that much more than just one Mopar branded sensor.

Gato28d

The shaking and quick loss of power seems to only happen im automatic because i just tried in 1 and 2nd gear and i dont feel the truck shaking and losing power but i still feel like im missing some power.