I know, I'm having the same problem for the past two days (right after the mx6 meet) -- except mine remains at 2000 rpm even when warm. I've tried the same troubleshooting steps, plus checked the vacuum lines (everything is connected), checked the accelerator cable too.
High idle on cold start
I've got a 1993 KLZE cuved neck, full JSPEC setup, and CAI. when i start the car cold it idles at 1800-2000 rpm, but when i run the car for 20 - 30 min, it idles fine. I've tried cleaning the TB, adjusting the idle screw and TPS. I can't think of any thing else. I'm tired of wasting gas at stop lights :S.
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Di either of you bypass the coolant lines to the TB? because that will cause some idle issues. for BShark try checking your IAC valve, if it's stuck open that would definitely cause a high idle. I also noticed both of you are Canadian, it is getting colder up here now so perhapse thats causeing the motor to idle high for longer periods, i know mine always does this in the winter.
No its not that much colder here, maybe a few degrees, but nothing major. I installed a new IAC a couple weeks ago, that didn't do anything. I've cleaned the TB check all vacuum lines, i have an EGR bolted on but not connected in the vacuum or coolant system. I don't have the bypass mod. Any other ideas???? i'm wasting gas :s.
when it's idleing high try to see if you can close the TB any more with your hand, if you can maybe the spring in your TB is weak, cant think of anything else
Engine coolant temperature sensor. It's a 2-wire sensor, next to the timing belt cover, at the end of the fuel injector rails. If the resistance is too high, it thinks the engine is very cold, and raises the idle to very cold morning setting. First clean the connection, and if that doesn't work, get your multimeter set on ohms, and measure the resistance of the sensor against the specs here: 1993-1995 Engine Controller Malfunction Codes
One other thing to check: maybe you got the wires switched between the main ECTS (as above), and the special 93 ECTS(F), which controls the fans, and is located next to the coolant filler cap, next to the oil dipstick. Disconnect one of those two sensors, then check the codes. A disconnected main ECTS should give code 09; a disconnected ECTS(F) should give code 69. If you get the wrong code, you switched the wires. (It takes longer for the ECTS(F) to warm up, plus it has slightly different specs.)
One other thing to check: maybe you got the wires switched between the main ECTS (as above), and the special 93 ECTS(F), which controls the fans, and is located next to the coolant filler cap, next to the oil dipstick. Disconnect one of those two sensors, then check the codes. A disconnected main ECTS should give code 09; a disconnected ECTS(F) should give code 69. If you get the wrong code, you switched the wires. (It takes longer for the ECTS(F) to warm up, plus it has slightly different specs.)
Also, maybe the thermostat is stuck open. If the temp gauge stays on cold for too long, indicating that the engine takes a long time to warm up, the idle speed will stay high until it does eventually warm up.
well now that the weather has actually dropped below zero it has gotten alot better. so its prob. a thermostat prob.?
I still can't figure this out, its better but still not great. Once the idle settles down after a few minutes it bounces from 800 - 1800rpm. I have a new IAC, TB. also check the thermostat and it was ok. I'm out of ideas
I think it has to do with the TB because if its idling high and i push the throttle closed the idle drops, but i've cleaned it very thoroughly. My throttle linkage is a little loose..i can't think of anything else...any ideas
???
???
didn't you not have this issue before i belive it's your IAC that's messed up~
any idea what color the plugs are for the different connectors? after my ZE swap, I have an extra plug because on my ZE it lacks one of the coolant sensors.
I have a 93 and the ZE i got is a post 94 engine, hence the missing sensor. There is a green plug and a black or grey one I think. Right now I have the green plug plugged in and I'm wondering which is which.
oh yeah, my idle is also high when warmed up. When my engine is cold, my idle is perfect which makes me think it's because the missing sensor
I have a 93 and the ZE i got is a post 94 engine, hence the missing sensor. There is a green plug and a black or grey one I think. Right now I have the green plug plugged in and I'm wondering which is which.
oh yeah, my idle is also high when warmed up. When my engine is cold, my idle is perfect which makes me think it's because the missing sensor
Engine coolant temperature sensor. It's a 2-wire sensor, next to the timing belt cover, at the end of the fuel injector rails. If the resistance is too high, it thinks the engine is very cold, and raises the idle to very cold morning setting. First clean the connection, and if that doesn't work, get your multimeter set on ohms, and measure the resistance of the sensor against the specs here: 1993-1995 Engine Controller Malfunction Codes
One other thing to check: maybe you got the wires switched between the main ECTS (as above), and the special 93 ECTS(F), which controls the fans, and is located next to the coolant filler cap, next to the oil dipstick. Disconnect one of those two sensors, then check the codes. A disconnected main ECTS should give code 09; a disconnected ECTS(F) should give code 69. If you get the wrong code, you switched the wires. (It takes longer for the ECTS(F) to warm up, plus it has slightly different specs.)
The green plug should be connected to the temp sensor next to the fuel injector rails. To double check, check the codes. If you get code 9, the main ECTS is not plugged in. If you get code 69, the ECTS for the fans is not plugged in.
Since you have a 93, I think you will need to add the fan sensor from your old 93 engine, so the fans get controlled properly. I assume your fans come on all the time?
Since you have a 93, I think you will need to add the fan sensor from your old 93 engine, so the fans get controlled properly. I assume your fans come on all the time?
I replaced it (IAC) but i think its just the TB sticking, but i can't figure out how to fix it
my fans come on really early and stay on all the time at like full blast 
I bought another coolant sensor, gotta drill and tap or have someone else drill and tap the hole for the sensor. been trying to locate an elbow with the sensors already in it, but anthrax (who has one) seems a little busy, plus to change that elbow is a pita
I bought another coolant sensor, gotta drill and tap or have someone else drill and tap the hole for the sensor. been trying to locate an elbow with the sensors already in it, but anthrax (who has one) seems a little busy, plus to change that elbow is a pitaThe green plug should be connected to the temp sensor next to the fuel injector rails. To double check, check the codes. If you get code 9, the main ECTS is not plugged in. If you get code 69, the ECTS for the fans is not plugged in.
Since you have a 93, I think you will need to add the fan sensor from your old 93 engine, so the fans get controlled properly. I assume your fans come on all the time?
Ya my fan does the same thing
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