Idle bounces when cold after setting tps
Idle bounces when cold after setting tps
After pulling the ic, changing the plugs, i decided to adjust the tps. Didnt have the LED's that i thought i had, so i went to radioshack, picked some up. by the time i came back, the car was pretty much cooled down. I adjusted the tps anyway, and now it runs like a bag of **** when warming up. Specifically, a bouncing idle. However, when it stabilizes, the idle is rock solid.
Is it because I adjusted the tps when it was cold?
Thanks!
-Ross
Is it because I adjusted the tps when it was cold?
Thanks!
-Ross
IF the motor is runnig fine when warm and just bounces when cold it's your vacuum switch. It regulates the vacuum when the motor warm up. If it is not working properly it will bounce your idle. After you chnge it out then adjust your TPS.
And just where might be this vacuum switch? Darn. I've three cars and each is without this vacuum switch. I been robbed!
Fingers........tps HAS to be set when the car is HOT. There is a thing called a fast idle cam that moves the throttle linkage as the car is warmed up. If the throttle linkage moves....the tps plunger moves. TPS plunger moves, the output voltage changes.
Normally a tps will have a output of 1volt when warm/hot. When and as the engine cools down, the voltage increases til when the engine is stone dead cold, the output reading from the TPS will be like 1.95 volts. All due to the thermowax and fast idle cam relationship.
Fingers........tps HAS to be set when the car is HOT. There is a thing called a fast idle cam that moves the throttle linkage as the car is warmed up. If the throttle linkage moves....the tps plunger moves. TPS plunger moves, the output voltage changes.
Normally a tps will have a output of 1volt when warm/hot. When and as the engine cools down, the voltage increases til when the engine is stone dead cold, the output reading from the TPS will be like 1.95 volts. All due to the thermowax and fast idle cam relationship.
Last edited by HAILERS; Apr 15, 2003 at 10:57 AM.
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Ok that's what I thought. Thanks hailers. Because the TPS was WAYYYYYYYYYYYYYYYYYYY off... like.. 20-30 turns of the screw driver off!!!!!!
I figured i misadjusted it. Stupid me. *hangs his head in shame and buys a honda*
I figured i misadjusted it. Stupid me. *hangs his head in shame and buys a honda*
I think it is theoretically possible but it is a serious PITA. The problem is that when you push the screwdriver in the throttle body will open so you can't get much push on the screw.
****** have never heard of any vacuum switch. Is this a joke??*******
No sooner do I reply as I did in a earlier reply.....than I read a thread asking "What this is?" and Icemark says its a vacuum switch for the automatic transmission. Oh well. But then again, nobody, and I mean nobody owns a automatic transmission RX.
No sooner do I reply as I did in a earlier reply.....than I read a thread asking "What this is?" and Icemark says its a vacuum switch for the automatic transmission. Oh well. But then again, nobody, and I mean nobody owns a automatic transmission RX.
Re-adjusted tps. Works fine now. Except on warm restart, it starts with a low idle and slowly creeps up! This car has the idle gremlins like crazy.
Is there a warm start-up idle adjustment anywhere? This is getting to be absurd
sorry guys!
Is there a warm start-up idle adjustment anywhere? This is getting to be absurd
sorry guys!
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I know there was a post about a guy who set it when cold and it was bad and then set it again when warm and it worked fine.
