Rpm's keep dropping

1993 LEXUS LS 400
180,000 MILES • 3.6L • V8 • 2WD • AUTOMATIC
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CALLMEREY
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I just finished changing my timing belt and everything was adjusted and all cams were lined-up at TDC. I ran the engine and it idles okay at 650 rpm, then I slowly step on the gas pedal to increase rpm's and when in reaches 1000 rpm's, it drops to zero. I continued stepping on the gas pedal but no power increase. I also tried adjusting the throttle sensor, but no help. Please advise on how can i fix it.
Dec 16, 2017 at 1:38 PM
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ASEMASTER6371
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Good morning my name is Roy and I will assist.

From your description it sounds like you need a throttle position sensor for the fly by wire system. has nothing to do with the repair unless this issue was present prior to your repair.

if the proper signal is not sent to the ECM it will cause this. just to be sure, is there an accelerator cable on the throttle body?

Roy
Dec 17, 2017 at 6:21 AM
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CALLMEREY
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lexus 1993 ls400,
i've replaced timing belt and everything is tdc lined up. I also replaced my throttle sensor, replaced all ignition plugs and wires, but eng idles ok but won't increase rpm, also I could smell raw fuel, please help me figure out this problem.
Jan 23, 2018 at 2:24 PM
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ASEMASTER6371
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was this issue present before the timing belt repair???

Roy
Jan 24, 2018 at 1:40 AM
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CALLMEREY
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Thank you for your response, Roy. This issue was not present before the timing belt repair.
Jan 24, 2018 at 3:37 PM
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ASEMASTER6371
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Good morning

Double check all your vacuum lines for any that may be cracked or broken. Make sure the plate in the throttle is clean of all carbon as well.
Also, re verify your timing marks. the mark on the back head is the hardest to see and can be off 1 tooth and cause this issue.

Roy
Jan 25, 2018 at 1:01 AM