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Reduced Engine Power Problem..HELP!!!

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Old Dec 1, 2007 | 12:03 PM
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Default Reduced Engine Power Problem..HELP!!!

Hey guys,
Car ran fine all the way to work yesterday untill i got about 5 mins away after taking off from a stop light the REDUCED ENGINE POWER came on. I tried clearing the code and would not clear. I finally was able to drive it 10mph down the freeway to my work. I pulled the battery terminal to reset the pcm and it did. As soon as I started the car it came right back on. I checked the code its coming up PCM 1221 H C which shows Throttle Body Positioning Sensor or if I'm wrong please tell me. So I swapped the black cyliner part of the throttle body out and its still doing it. What else could it be? I was told the pcm plug might be dirty. I checked that and seemed fine. Any help would be appreciated..I"m going crazy having to leave my car there all weekend Thank you in advance for everyones help
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Old Dec 1, 2007 | 03:12 PM
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My '98 does this sometimes.....just shut down and start up again, then clear code....all is fine. Just seems to happen

I remember an old post where it said replace the TPS or make sure grounds are clean. I did not do anything with mine yet.

Last edited by RedC5; Dec 1, 2007 at 03:16 PM.
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Old Dec 1, 2007 | 06:16 PM
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Originally Posted by 99Silverbullet
Hey guys,
Car ran fine all the way to work yesterday untill i got about 5 mins away after taking off from a stop light the REDUCED ENGINE POWER came on. I tried clearing the code and would not clear. I finally was able to drive it 10mph down the freeway to my work. I pulled the battery terminal to reset the pcm and it did. As soon as I started the car it came right back on. I checked the code its coming up PCM 1221 H C which shows Throttle Body Positioning Sensor or if I'm wrong please tell me. So I swapped the black cyliner part of the throttle body out and its still doing it. What else could it be? I was told the pcm plug might be dirty. I checked that and seemed fine. Any help would be appreciated..I"m going crazy having to leave my car there all weekend Thank you in advance for everyones help
Mine did the same thing when I pulled it off to port and polish my throttle body. I thought I was being careful, but they are fragile. I got to work in mine fine, but when I went to start it after work, I got the reduced power. I took it off and tightened up the metal ring that holds the brushes in and it got me home, barely. I bought a new one and all was good.







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Old Dec 1, 2007 | 06:26 PM
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99Silverbullet

Did you replace the sensor or TB Motor??? I hope just the sensor!

There isn't really any grounds associated with this circuit to speak of. Its a discrete circuit that involves the Throttle position sensor, the accelerator peddle position sensor and the Throttle Actuator Computer (TAC) module. Check the wires (all of them ) from the throttle position sensor to the back of the engine. LOOK FOR DAMAGED WIRES at the rear of the engine near a black metal bracket!

BC
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Old Dec 1, 2007 | 07:34 PM
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thanks guys..i will try that and see what happens, give you an update tomorrow..have a good evening!
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Old Dec 2, 2007 | 06:05 PM
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hey guys..i switched that sensor out and cleaned the plug...seem to fix the prob..we'll see after i start it up a few more times..thanks again for everyones help..have a good week
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