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Help with code #121

Old Sep 25, 2004 | 05:57 PM
  #1  
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95f150
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From: Alberta
Help with code #121

Hello all,

95 f150 4x4
302 5spd

I have been noticing problems with my truck which seems to be a throttle problem, its been like this for awhile. I pulled the codes today with a code reader and got code #121. I did the KOEO test. The manual says this code is " closed throttle TPS voltage higher or lower than expected"

Should i change out the TPS? or is there something else i should be doing? Thanks,
Rob
 
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Old Sep 26, 2004 | 07:55 AM
  #2  
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EPNCSU2006
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Joined: Nov 2002
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From: Concord, NC
Test the TPS with a volt meter and see what the voltage values are. Measure between the green wire and the black wire with the tps harness plugged in, and the key on, engine off. Closed throttle should be right around .9V, and then voltage should smoothly increase to around 4.8V at full throttle. If the voltage change spikes (doesn't change smoothly), it's time to replace the tps.
 
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