Unusually High Idle.. (99 SS Auto)
Ok, another thread around the same time as yours, sorry. My questions are still the same though...air is getting in somewhere...if you can hook up to a scanner and look at the maf g you *might* be able to see if it is being metered...ie tb or iac stuck open. You'd need to play with that, not sure if youd be able to tell. If the air is not being metered you have a vacuum leak.
did you ever find the problem? I have the exact same problem with my 96 firebird, idle about 1200 then warms up to about 1500 rpms... I have done the following... replaced the TB gasket, took out my catalytic converter - it was clogged apparently, checked my tps sensor (good), MAF sensor (good) and can't find a vacuum leak
here is what the weird thing is.... I took a small wrench and pried up on the tb plate a little and held it there... until my rpms sounded about right for idle....after holding it in that position for about 30 sec. and stopped the prying/ the engine stayed at a constant normal idle. (WEIRD)
I turned the AC on and off to see if it would jump up in rpms slightly and then go back down like it should ( it did)---good... I took it for a test drive and MY CAR DID NOT WANT TO SHIFT UNTIL (3500) rpm's and it shifts hard as hell. what the hell? (automatic trans.)
My tb plate is not even touching the set screw I made sure of that..im thinking that it may be a pcm or ecm issue seeing how I can actually almost (trick) it into ideling normal just by prying on the tb plate and holding it there for about 30 sec. I would REALLY like to know what's going on I'm clueless.
here is what the weird thing is.... I took a small wrench and pried up on the tb plate a little and held it there... until my rpms sounded about right for idle....after holding it in that position for about 30 sec. and stopped the prying/ the engine stayed at a constant normal idle. (WEIRD)
I turned the AC on and off to see if it would jump up in rpms slightly and then go back down like it should ( it did)---good... I took it for a test drive and MY CAR DID NOT WANT TO SHIFT UNTIL (3500) rpm's and it shifts hard as hell. what the hell? (automatic trans.)
My tb plate is not even touching the set screw I made sure of that..im thinking that it may be a pcm or ecm issue seeing how I can actually almost (trick) it into ideling normal just by prying on the tb plate and holding it there for about 30 sec. I would REALLY like to know what's going on I'm clueless.
Thread Starter
Teching In
Joined: Jun 2012
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Thanks for every ones different types of suggestions! I ran through almost every type of vacuum issue possible. However the peeps who suggested the TPS. Throttle position sensor.. were Right! $31 bucks later my car works again. I now know exactly why it failed too. Its 100% my dumb a$$ fault.
When I did a gasket over haul on my motor, it took the Throttle body off and cleaned all the oil and grime build up off by using simple green and a pressure hoes. This isn't bad unless you leave the sensors on like my dumb a $$ did. Which explains why the motor did run fine then change idles. Water built up inside the sensor, which leaked through the throttle bearing. When I took the TPS off it was filled with white crap and moisture. I almost instantly knew this wasn't right and was probably the problem. I then put it back together and did an idle reset and she runs GGGGGGrrrrrrrrate!
Thanks again LS1techers!
When I did a gasket over haul on my motor, it took the Throttle body off and cleaned all the oil and grime build up off by using simple green and a pressure hoes. This isn't bad unless you leave the sensors on like my dumb a $$ did. Which explains why the motor did run fine then change idles. Water built up inside the sensor, which leaked through the throttle bearing. When I took the TPS off it was filled with white crap and moisture. I almost instantly knew this wasn't right and was probably the problem. I then put it back together and did an idle reset and she runs GGGGGGrrrrrrrrate!
Thanks again LS1techers!
how do i do an idle relearn process I'm still trouble shooting my firebird idel issues.... I just checked to make sure the pcm was getting correct voltage from the signal wire from my tps sensor and it is.... But I would like to do the idel relearn thing you are talking about and try that.
Throttle/Idle Learn
Idle Learn Procedure
Anytime the powertrain control module (PCM) or the battery is disconnected, the PCM loses power, or the PCM is reprogrammed, the PCMs learned idle position is lost. The engine idle is unstable when the learned idle position is lost.
Perform the following procedure in order to return the learned idle to the correct position:
Automatic Transmission
Turn OFF the ignition.
Restore the PCM battery feed.
Turn OFF the A/C controls.
Set the parking brake and block the drive wheels.
Start the engine.
Ensure that the engine coolant temperature is more than 80°C (176°F).
Shift the transmission into Drive.
Allow the engine to idle for 5 minutes.
Shift the transmission into Park.
Allow the engine to idle for 5 minutes.
Turn OFF the engine for 30 seconds.
Manual Transmission
Turn OFF the ignition.
Restore the PCM battery feed.
Turn OFF the A/C controls.
Set the parking brake and block the drive wheels.
Place the transmission in Neutral.
Start the engine.
Ensure that the engine coolant temperature is more than 80°C (176°F).
Allow the engine to idle for 5 minutes.
Turn OFF the engine for 30 seconds.
Idle Learn Procedure
Anytime the powertrain control module (PCM) or the battery is disconnected, the PCM loses power, or the PCM is reprogrammed, the PCMs learned idle position is lost. The engine idle is unstable when the learned idle position is lost.
Perform the following procedure in order to return the learned idle to the correct position:
Automatic Transmission
Turn OFF the ignition.
Restore the PCM battery feed.
Turn OFF the A/C controls.
Set the parking brake and block the drive wheels.
Start the engine.
Ensure that the engine coolant temperature is more than 80°C (176°F).
Shift the transmission into Drive.
Allow the engine to idle for 5 minutes.
Shift the transmission into Park.
Allow the engine to idle for 5 minutes.
Turn OFF the engine for 30 seconds.
Manual Transmission
Turn OFF the ignition.
Restore the PCM battery feed.
Turn OFF the A/C controls.
Set the parking brake and block the drive wheels.
Place the transmission in Neutral.
Start the engine.
Ensure that the engine coolant temperature is more than 80°C (176°F).
Allow the engine to idle for 5 minutes.
Turn OFF the engine for 30 seconds.
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Verdad Gallardo Thanks still not quite sure what you mean. My ***** are kind of messed up on my heater switch. So not really sure which on its on cause the **** just spins around freely.
I don't see any solenoid or red connector.
Is this the thing you were talking about or is it physically on the back of the intake?
I don't see any solenoid or red connector.
Is this the thing you were talking about or is it physically on the back of the intake?
