Throttle Surge and Cruise Control
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Bought a 1999 RX300 a couple weeks ago:
242,278 Miles (Today)
On about the 8th or 9th day I noticed that the Cruise Control stopped working. I figured I'd get to it later. A couple days later the surge started. I'll get up to 40 or so MPH. Take my foot off the gas, and the thing wants to keep speeding up. When I hit the brakes it will slow down but I can hear/feel that it still wants to run. After ****ting my pants I figured out that if I slide the transmission from Drive to Neutral it quickly runs up to 5000-6000 RPM then it seems to slip into a new gear, RPMs go down, I can put it back in Drive and the car performs normally for the rest of the drive. Engine light came on in conjunction with the surge starting.
Tried clearing the codes with a battery disconnect. No change. Engine light right back on.
Had a chance to stop by local parts store this morning to have them check the codes. Here's what I got:
P0125 Insufficient Coolant Temperature for closed loop fuel control
P1133 A/F ratio sensor circuit response malfunction (B1S1)
P1135 A/F ratio sensor heater circuit malfunction (B1S1)
P1153 A/F ratio sensor circuit response malfunction (B2S1)
P1155 A/F ratio sensor heater circuit malfunction (B2S1)
So obviously I need to replace both up-stream A/F ratio sensors. But I don't think they would have anything to do with my cruise control or the odd surge. I doubt the coolant temperature sensor would cause them either.
I was expecting some codes that would point to the Accelerator Position Sensor or the Throttle Position Sensor.
Here are my questions:
1) IF I replace these A/F sensors and the coolant temp sensor should I expect the Cruise Control to come back and/or the surge to go away?
2) Should I replace the APS and/or TPS sensors even though I am getting no fault codes for them?
3) IS there some other thing to check or fix that I am not even thinking about?
242,278 Miles (Today)
On about the 8th or 9th day I noticed that the Cruise Control stopped working. I figured I'd get to it later. A couple days later the surge started. I'll get up to 40 or so MPH. Take my foot off the gas, and the thing wants to keep speeding up. When I hit the brakes it will slow down but I can hear/feel that it still wants to run. After ****ting my pants I figured out that if I slide the transmission from Drive to Neutral it quickly runs up to 5000-6000 RPM then it seems to slip into a new gear, RPMs go down, I can put it back in Drive and the car performs normally for the rest of the drive. Engine light came on in conjunction with the surge starting.
Tried clearing the codes with a battery disconnect. No change. Engine light right back on.
Had a chance to stop by local parts store this morning to have them check the codes. Here's what I got:
P0125 Insufficient Coolant Temperature for closed loop fuel control
P1133 A/F ratio sensor circuit response malfunction (B1S1)
P1135 A/F ratio sensor heater circuit malfunction (B1S1)
P1153 A/F ratio sensor circuit response malfunction (B2S1)
P1155 A/F ratio sensor heater circuit malfunction (B2S1)
So obviously I need to replace both up-stream A/F ratio sensors. But I don't think they would have anything to do with my cruise control or the odd surge. I doubt the coolant temperature sensor would cause them either.
I was expecting some codes that would point to the Accelerator Position Sensor or the Throttle Position Sensor.
Here are my questions:
1) IF I replace these A/F sensors and the coolant temp sensor should I expect the Cruise Control to come back and/or the surge to go away?
2) Should I replace the APS and/or TPS sensors even though I am getting no fault codes for them?
3) IS there some other thing to check or fix that I am not even thinking about?
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There was a similar post a few days ago.
Throttle cable and cruise control cable are wound up on the wheel (pulley) that operates the butterfly. Check if that is operating freely and shuts close. Toyota/Lexus vehicles and other vehicles have had problems with the driver side carpet too, which prevents the gas pedal to return to the right position.
Have an assistant look at the pulley mentioned above as you depress the gas pedal (engine shut down).
Salim
Throttle cable and cruise control cable are wound up on the wheel (pulley) that operates the butterfly. Check if that is operating freely and shuts close. Toyota/Lexus vehicles and other vehicles have had problems with the driver side carpet too, which prevents the gas pedal to return to the right position.
Have an assistant look at the pulley mentioned above as you depress the gas pedal (engine shut down).
Salim
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Thanx for the info Salimshaw. I hadn't even considered a simple mechanical error.
When I got under the hood I saw that the bracket that holds/guides the cruise control cable just before the pulley had fallen off. Keeping the cruise control from working and tangling up the whole works. Someone had broken off the bolt that held it in place and tried LocTite instead.
I drilled out the hole. Zipped in a self tapper. Bingo-Bango.
When I got under the hood I saw that the bracket that holds/guides the cruise control cable just before the pulley had fallen off. Keeping the cruise control from working and tangling up the whole works. Someone had broken off the bolt that held it in place and tried LocTite instead.
I drilled out the hole. Zipped in a self tapper. Bingo-Bango.
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