I have a 2000 TJ, 2.5 L 5 speed. Drove it down to Florida from South Carolina. It drove just fine until after the first fuel up and then started sputtering and backfiring. Made it all the way, but now, when I drive to work in the morning (about a 30 min drive) it drives perfectly fine, but on the way home it starts doing it again after about 10-15 min of driving….
Sputtering and backfiring
- Thread starter TF60
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- backfiring sputtering
Do you know how to test a TPS? I can run you through it if you're interested. Could be a dead spot in the potentiometer that is exacerbated by the Florida heat. Wouldn't hurt to test fuel pressure either.
Check out your throttle body & IAC also. If you have a scan tool that does data logging hook it up and see if you can capture when it's happening as that might help pin point it.
What brand did you use? These engines can be sensitive to aftermarket sensors sometimes. Many try to use MOPAR only sensors
You hook a multimeter up and move the throttle watching the multimeter to see if it's smooth as you move the throttle. You're looking for dead spots.
Ok, I can’t remember what brand, it’s been awhile since I changed em. I’ll try with the Voltage meter
You will want to put your meter in 20VDC, put the positive probe on the feedback for the sensor, and put the negative probe to ground. Turn the key on. Move the throttle by hand slowly, and look for any positions where the feedback reads "OL" or 0 volts. You'll backprobe the connector pins with your leads.
You're reading the voltage drop across a variable resistor (that is fed 5V from the PCM) as you move the throttle by hand, which isn't really at all any different than what the PCM is constantly doing as you drive down the road. You want the positive probe on the orange and dark blue wire, and the negative probe on the brown and yellow wire. All of the wiring diagrams are included in the FSM that's linked on the forum. My 2003 had a similar problem when the TPS failed, and this was how I tested it (also had a CEL, so I got a little headstart). https://wranglertjforum.com/attachments/2000-tj-service-manual-pdf.362948/
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