... cured by disconnecting the TPS. Why?
While replacing the starter contacts, I disconnected the battery. Upon first startup, the idle was 600, and started dropping as the engine started warming up slightly. After a few minutes, the idle was 0. Many restarts and a dozen miles of driving have no effect. The IAC occasionally bumps the idle, but to no avail. AC will raise idle, but it will still stall after dropping to 150-200. What consistently solves the problem (I experimented...) is:
1. turn engine off.
2. unplug TPS
3. turn engine on and keep RPMs at 600-1000 for 10 seconds or so (the CEL obviously comes on)
4. turn engine off
5. plug TPS back in
6. turn engine on and enjoy reasonable idle.
The LC is a '94. The air hose is new. No obvious vacuum leaks. New throttle cable, but similar behavior observed with old, rotten cable. Plugs, wires, distributor cap all new. TPS not checked (next step). The normal idle is 550, and occasionally erratic. I'm still catching up on maintenance.
Question: What exactly is going on? How can unplugging the TPS possibly cure these symptoms? What should I look for when I take it off in the next couple of days and start following the FSM. And how do I apply vacuum to the TPS?
I did search, I did read the 170+ posts found, I got inspired to do more AR maintenance and I apologize for not finding an answer in the collective repository of mud wisdom
Thank you in advance!
While replacing the starter contacts, I disconnected the battery. Upon first startup, the idle was 600, and started dropping as the engine started warming up slightly. After a few minutes, the idle was 0. Many restarts and a dozen miles of driving have no effect. The IAC occasionally bumps the idle, but to no avail. AC will raise idle, but it will still stall after dropping to 150-200. What consistently solves the problem (I experimented...) is:
1. turn engine off.
2. unplug TPS
3. turn engine on and keep RPMs at 600-1000 for 10 seconds or so (the CEL obviously comes on)
4. turn engine off
5. plug TPS back in
6. turn engine on and enjoy reasonable idle.
The LC is a '94. The air hose is new. No obvious vacuum leaks. New throttle cable, but similar behavior observed with old, rotten cable. Plugs, wires, distributor cap all new. TPS not checked (next step). The normal idle is 550, and occasionally erratic. I'm still catching up on maintenance.
Question: What exactly is going on? How can unplugging the TPS possibly cure these symptoms? What should I look for when I take it off in the next couple of days and start following the FSM. And how do I apply vacuum to the TPS?
I did search, I did read the 170+ posts found, I got inspired to do more AR maintenance and I apologize for not finding an answer in the collective repository of mud wisdom
Thank you in advance!