Idle hang in gear
03-31-24, 04:15 PM
#1
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Thread Starter
Idle hang in gear
Alright, so went through the car and fixed alot of issues it was having electrical wise and changed the pads (hawk) and all hardware for the front brakes. Now some new things have reared their ugly heads and I can't find alot of info pertaining to what's happening. 1st there is a clunking noise from the front right of the car when I brake. Pretty sure the pads are moving in the caliper. I'm pretty sure I'm not missing any pieces of hardware unless they were missing when I bought the car. The 2nd issue is idle hang ONLY while in gear. If I put the car in neutral, the idle drops back down from 1300-1500 to around 600-800. But if im in any gear, even with the clutch depressed, it hangs if revved passed a certain point.
04-12-24, 06:04 PM
#4
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Ohhh, by hang you mean the idle stays high even after the engine is warmed up, but only while it is in gear? I thought you meant it was stumbling like it does when it doesn't get enough fuel. Your actual problem is high idle under load.
Only a few things I know would cause that:
Thermowax: Not likely as the high idle only occurs under load. The thermowax is a purely mechanical/physical part controlled by temperature not by anything electrical to my knowledge. There are only one or two vacuum lines running off it.
Bypass Air Control(BAC): They can get stuck open and result in high idle. But.... Same as thermowax here, if it was stuck it wouldn't lower when you were in neutral. Unplug it.
Air Supply Valve(ASV): I am pretty sure I removed this thing off my engine. It's sitting here on my desk because the wiring broke. It wouldn't be stuck open in your case, it would have to be malfunctioning or something would be sending it a bad signal. Unless I am mistaken it gets sent a 12v signal for like 30 seconds when you start the engine and shuts off completely. If it stayed on for whatever reason it would cause a high idle. Unplug it.
Throttle Position Sensor(TPS): I have yet to set one of these that will remain in spec for over a month. In theory the ECU should automatically compensate for it. I would start checking here. Do the recommended testing the FSM for it.
Only a few things I know would cause that:
Thermowax: Not likely as the high idle only occurs under load. The thermowax is a purely mechanical/physical part controlled by temperature not by anything electrical to my knowledge. There are only one or two vacuum lines running off it.
Bypass Air Control(BAC): They can get stuck open and result in high idle. But.... Same as thermowax here, if it was stuck it wouldn't lower when you were in neutral. Unplug it.
Air Supply Valve(ASV): I am pretty sure I removed this thing off my engine. It's sitting here on my desk because the wiring broke. It wouldn't be stuck open in your case, it would have to be malfunctioning or something would be sending it a bad signal. Unless I am mistaken it gets sent a 12v signal for like 30 seconds when you start the engine and shuts off completely. If it stayed on for whatever reason it would cause a high idle. Unplug it.
Throttle Position Sensor(TPS): I have yet to set one of these that will remain in spec for over a month. In theory the ECU should automatically compensate for it. I would start checking here. Do the recommended testing the FSM for it.
04-12-24, 06:15 PM
#5
Junior Member
Thread Starter
Ohhh, by hang you mean the idle stays high even after the engine is warmed up, but only while it is in gear? I thought you meant it was stumbling like it does when it doesn't get enough fuel. Your actual problem is high idle under load.
Only a few things I know would cause that:
Thermowax: Not likely as the high idle only occurs under load. The thermowax is a purely mechanical/physical part controlled by temperature not by anything electrical to my knowledge. There are only one or two vacuum lines running off it.
Bypass Air Control(BAC): They can get stuck open and result in high idle. But.... Same as thermowax here, if it was stuck it wouldn't lower when you were in neutral. Unplug it.
Air Supply Valve(ASV): I am pretty sure I removed this thing off my engine. It's sitting here on my desk because the wiring broke. It wouldn't be stuck open in your case, it would have to be malfunctioning or something would be sending it a bad signal. Unless I am mistaken it gets sent a 12v signal for like 30 seconds when you start the engine and shuts off completely. If it stayed on for whatever reason it would cause a high idle. Unplug it.
Throttle Position Sensor(TPS): I have yet to set one of these that will remain in spec for over a month. In theory the ECU should automatically compensate for it. I would start checking here. Do the recommended testing the FSM for it.
Only a few things I know would cause that:
Thermowax: Not likely as the high idle only occurs under load. The thermowax is a purely mechanical/physical part controlled by temperature not by anything electrical to my knowledge. There are only one or two vacuum lines running off it.
Bypass Air Control(BAC): They can get stuck open and result in high idle. But.... Same as thermowax here, if it was stuck it wouldn't lower when you were in neutral. Unplug it.
Air Supply Valve(ASV): I am pretty sure I removed this thing off my engine. It's sitting here on my desk because the wiring broke. It wouldn't be stuck open in your case, it would have to be malfunctioning or something would be sending it a bad signal. Unless I am mistaken it gets sent a 12v signal for like 30 seconds when you start the engine and shuts off completely. If it stayed on for whatever reason it would cause a high idle. Unplug it.
Throttle Position Sensor(TPS): I have yet to set one of these that will remain in spec for over a month. In theory the ECU should automatically compensate for it. I would start checking here. Do the recommended testing the FSM for it.
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