1997 Jeep Wrangler Hesitation

1997 JEEP WRANGLER
125,000 MILES • 4 CYL • 4WD • MANUAL
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STEVENWERTH
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IN my 97 Wrangler 2.5l Manual Trans, When I start to drive (EVERY time) I get about a 1/4 mile and it hesitates, hot or cold. If I keep accelerating it just stalls (doesn't kill the engine). Once I let off the accelerator and clutch and them pump the accelerator it kicks back in and doesn't do it again until I turn off the car and then drive it again.

I have Changed both O2 sensors, new manifold, new plugs and wires, and replaced the MAP sensor.

Any suggestions on what this might be?

Thanks
Dec 3, 2008 at 4:47 PM
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JAMES W.
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Do you have, or have you had, A check engine light recently? I would be suspicious of the throttle position sensor, but a little more information will help narrow it down. Please advise.
Dec 3, 2008 at 9:23 PM
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STEVENWERTH
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The check engine light will come on periodically and stay on a couple days and then go off for about a week, then repeats.
Dec 4, 2008 at 9:56 AM
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JAMES W.
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What ever is tripping your check engine light could be a valuable clue to your problem. Auto Zone, and most moast other parts stores will scan your computer for free. If you will have this done and let me know comes up, we can go from there. Please advise.
Dec 4, 2008 at 11:24 AM
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STEVENWERTH
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Actually, I bought one online that I think is going to help. It should be here today. I will wait for the check engine light to come on and then let you know what the code is. I have to say, this is a GREAT resource for help. Thanks for this service.
Dec 4, 2008 at 12:11 PM
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JAMES W.
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All the moderators here enjoy sharing experience, not only with the posters, but with each other. What ever tripped your check engine light will be stored in the computer's memory. You can scan the memory any time, even if the CEL is not on.
Dec 4, 2008 at 5:15 PM
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STEVENWERTH
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I used the ignition ON-OFF ON-OFF ON mode and it gave me the following codes:

22: Engine coolant temperature sensor above or below acceptable voltage.

12: Direct battery input to PCM was disconnected within the last 50 Key-on cycles.

14: MAP sensor input above or below acceptable voltage. 5 volt output to MAP sensor open.

Interestingly enough I put a new MAP sensor in the other day and my diagnostic OBD machine said it was at 5 volts

When I hooked up the OBD machine I just got today, it gave me trouble codes:

P0118 (M)
Engine Coolant Temperature Circuit High Input
Engine coolant temperature sensor input above the maximum acceptable voltage.

P0108 (M)
Manifold Absolute Pressure/Barometric Pressure Circuit High Input
MAP sensor input above maximum acceptable voltage.
Dec 4, 2008 at 5:38 PM
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JAMES W.
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I would go ahead and change the temp sensor, clear all the codes and see what comes up in the next day or two. The CTS input will have a bearing on map sensor processing. Let me know.
Dec 4, 2008 at 6:21 PM
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STEVENWERTH
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Where is the Temp Sensor?

I just took it for a drive with the ScanGuage installed.
The coolant temp leveled out at 195 degrees and the MAP was 5 PSI at Idle and maxed out around 13.5- 14 PSI at full accelleration. I read that up to 15 PSI is normal. I am not sure if this helps......
Thanks
Dec 4, 2008 at 6:23 PM
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JAMES W.
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Check to see what the temp sensor reads when you start it up cold.
Dec 4, 2008 at 6:51 PM
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STEVENWERTH
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I replaced the CTS and it still gives me the same trouble codes. The CEL is not lit but, I am still getting those same codes. So, I have replaced the MAP and CTS sensors and still nothing.
Thank you so much for the help so far.
Dec 4, 2008 at 9:19 PM
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STEVENWERTH
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The car temperature was 80 degrees at start-up. I changed the CTS Thursday and gave it the weekend and it still gives me the same 2 error codes. I am stumped.
Dec 8, 2008 at 10:44 AM
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JAMES W.
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Lets see if your computer is telling us the truth. Clear all the codes and unplug the CTS, and take it for a spin. We'll see if sets a code. It may be a problem with the ECM. I'm always hesitant to blame the computer, but this may be an exception.
Dec 8, 2008 at 1:32 PM
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STEVENWERTH
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I unplugged the CTS, cleared the codes, and then drove it. The check Engine Light came on. It was still giving me the same 2 codes. I got home and plugged the CTS back up and the CEL was still on and I still got the same 2 codes.
Dec 8, 2008 at 3:26 PM
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JAMES W.
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One more check. Unplug the throttle position sensor. Stsrt the Jeep and just let it idle for 5-10 minuites and see if it sets a code.
Dec 10, 2008 at 11:39 AM
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STEVENWERTH
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I replaced the Throttle Position Sensor with a new one and now I get the same 2 errors plus, P0123 now.
Dec 16, 2008 at 3:21 PM
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JAMES W.
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The new code that was set,0123, is for the TPS you just installed. I've noticed, all the components you have replaced "reading high". How much have you driven your jeep since we started on this little project. The reason I ask is, the ecm has to go through a relearn process to recalibrate itself to the new parts. It may not have completed it yet. I'm trying to find out how long this process is supposed to take, but it's a little confusing.
Dec 16, 2008 at 8:34 PM
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STEVENWERTH
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I work from home so I am lucky to drive it a couple miles per day. I have noticed it runs better but, it still hesitates, just not as hard.
Dec 19, 2008 at 7:10 PM
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JAMES W.
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Let me know what transpires in the next couple of days.
Dec 19, 2008 at 8:06 PM