Engine sputter

[passatdiesel]

97 TJ 2.5L

Under moderate acceleration, I get hestitation from the engine.
Replaced spark plug wires, regapped spark plugs and cleaned distributor cap. Problem still occurs. Under heavy accel. no sputtering, or while maintaining speed. Just when you apply a little more pressure to the accelerator, the Jeep starts to miss and shake. Going to go get the fuel rail pressure checked. Where else to go from here, I'm open to suggestions. Someone else had a similar problem on and old post, and was told to check the EGR sensor, where would that be located?

[frenchy]

O2 sensor ever been changed?

[passatdiesel]

Nope, never changed the 02 sensor. What are the symptoms of a defective sensor?

[TJ54]

TPS, throttle position sensor. Maybe,
The dealer is the cheapest, about $8o
Easy to replace, Two screws

[01sahara]

Is the engine throwing any error codes? They are easy to read on the newer models I don’t know how to on the older ones but the info should be on line if you search the web. If you have not checked it might narrow the possibilities before buying more parts.

[passatdiesel]

Just bought an odb2 reader from NAPA that was on sale for $80
I'll try and see if it works tomorrow, otherwise I can just return it if I find it doesn't help.  So far no check engine light has come on yet, but from what I've read, some codes won't throw a CEL

[TJ54]

To get the codes from your 1997 TJ:

1) Turn the ignition key ON THREE TIMES in succession:
ON : OFF : ON : OFF : ON
(within FIVE seconds)

2) Count the number of times the check engine lamp on the dash flashes. The number of flashes represents the error code. There will be a short pause between the flashes representing the different digits of the code. Longer pauses separate individual trouble codes.

3) Code 55 will be the last code to be displayed.

4) These codes will also be displayed on the odometer, where they are much easier to read!


Google  "TJ error codes"  you will find a page that explains the codes.

http://www.webejeepin.com/Check-Engine.htm

I don't know if having an actual OBD2 reader will tell you more.

[passatdiesel]

It threw two codes, 121 and 123 ODB.
Throddle/petal sensor voltage too high (out of range)
$115 at napa, and we'll see tomorrow if it works or not.

[passatdiesel]

Sure enough it was the throddle sensor... Man, she runs better then the day i bought it...

[passatdiesel]

Installations should be fool proof or so I thought.
after the sensor installation, I find the engine idles at 2,000 rpm untill I put the engine under load, after the engine warms up, it kicks down to around 1,000 rpm. I'm going to try when i have more time, to take the sensor off and try to install it again, the slotted shaft may have been misalligned to the sensor. See how that goes.