ramaker2

My 94 xj has been driving at higher rpms regardless of the speed. It drives smooth but with slight loss of power. It Idles smoothly at normal rpms but starts high. The symptoms occurred fairly abruptly. All of my fluids are good and my transmission is behaving normally. When I touch the accelerator it has an oh so slight hesitation before it reacts. Any help would be appreciated.
No engine light.

98xjuser

I had this issue and it was my crankshaft position sensor. After replacing it the idle speed was very high after multiple test drives and I had to get a second replacement. After you change the sensor make sure you hold the battery terminals against eachother for a good minute to drain the capacitors and reset the computer.

hope that helps. Sort of an easy and cheap fix

edit:
the sensors in your throttle body. While you change it make sure to also check the throttle position sensor as it's known to go out on jeeps. My issue was both sensors

ramaker2

Thank you for the advice. I hope that works 👍

downs

Define "higher rpms" and at what speed. Ive got a feeling your torque converter isnt locking.

Also a higher idle speed at first start is normal. Espeically during colder weather. As the engine warms up the computer will adjust the IAC accordingl .

downs

The crankshaft position sensor isnt in the throttle body. Are you sure youre not talking avout the idle air controller?

ramaker2

Regardless of my speed, the rpms are consistently higher. They’re not at anything crazy but at 2000 at 65mph which is higher than normal (around 1750). And if I’m driving at lower speeds they’re about 500rpm faster than normal.
The jump in rpm is consistent even after overdrive kicks in. I’ve also tried throwing it in other gears like 3rd and they jump even higher like you would expect
oh and I know higher idle speed at first start is normal, but mine has been even HIGHER than normal. Just enough to where you can audibly notice it

downs

When cruising at 65 next time. Tap the brake pedal just enough to make the brake lights come on. See if you see an increase in RPM. If not your torque converter isnt locking. Its the only thing that will make you run higher than normal RPMs at cruising speed.

ramaker2

I will do that. Thank you for your help

98xjuser

yup I was talking about the idle air control valve. My bad forgot the name but remembered the issue. Thanks for the correction

bluejeep2001

Don't know how your turning so slow...I am running 31's on a 3.55 dana 35c and the auto tranny. At a gps verified 65 I am running almost exactly 2000 in OD...If I keep gentle press on gas and touch brake pedal...rpm's increase 200-300. If I shift into 3 I shoot up to above 2500 but then it drops to 2300 ballpark...Seems to run just like my old one with the 31's on it...they were both stock...then lifted then stroked...Cant imagine turning that slow at 65 unless you changed wheels and didn't sync the speedo gear...Do you Idle at approx. the 3rd hash mark on the tach...that's standard...Mine idles a hair below it but it varies a little...the colder the engine the higher it idles