Bad clutch switch? idle surges
Passenger
Posts: n/a
From: So. CaL
Bad clutch switch? idle surges
EACH and EVERY time i push the clutch pedal in (let's say at idle), the RPM's would fluctuate annoyingly! and won't stop until i release the clutch pedal. REALLY irritating when i'm trying to be silent around my quiet neighborhood...
at first i thought it was some kind of a vacuum leak, but after doing some investigating, i found that it was the clutch switch.
what i did was push the clutch pedal down during idle (which caused the idle to fluctuate), and while HOLDING THE PEDAL DOWN, i pushed down the clutch switch (little button placed in front of the top part of the clutch pedal), and "WALLA... no more fluctuating!!!
i was very pleased to have discovered what the cause was to this "clutch-in idle surge" problem (which i have dealt with for years now!), but............ i don't know how to address the issue!
how can i fix this problem? get a new clutch switch??
and HOW the heck does this stupid switch have anything to do with my idle?! i'm guessing the switch is bad, and is throwing error codes at the ECU, which then tries to correct itself¿
it seems like i'm the only member on this forum with this problem (did searches and found nothing), so ANY INPUT/ADVICE would be GREATLY appreciated!
thanks for reading people
have a nice day!!!
at first i thought it was some kind of a vacuum leak, but after doing some investigating, i found that it was the clutch switch.
what i did was push the clutch pedal down during idle (which caused the idle to fluctuate), and while HOLDING THE PEDAL DOWN, i pushed down the clutch switch (little button placed in front of the top part of the clutch pedal), and "WALLA... no more fluctuating!!!
i was very pleased to have discovered what the cause was to this "clutch-in idle surge" problem (which i have dealt with for years now!), but............ i don't know how to address the issue!
how can i fix this problem? get a new clutch switch??
and HOW the heck does this stupid switch have anything to do with my idle?! i'm guessing the switch is bad, and is throwing error codes at the ECU, which then tries to correct itself¿
it seems like i'm the only member on this forum with this problem (did searches and found nothing), so ANY INPUT/ADVICE would be GREATLY appreciated!
thanks for reading people
have a nice day!!!
Passenger
Posts: n/a
From: So. CaL
^ okay. i went ahead and unplugged the clutch switch (there was two plugs coming from the switch, i unplugged the one with a yellow and a black wire) and it worked! no more idle surge when clutch in.... BUT
the idle bumps up about 200-300 RPM's when i push in the clutch (which is way better than the idle bouncing btw)... now, can i get an explanation on that? why would the clutch pedal have an affect on idling?
§ just added § hmmm...
http://forum.teamfc3s.org/showthread...=clutch+switch
guess i should get a new one....
so pretty much unplugging the switch solved the problem. (thanks rotorman85!!!), but i am still kinda stumped
i have to push the clutch pedal down in order for the car to start, and by unplugging the clutch switch, i was assuming i didn't have to do that anymore, BUT i still do... so my question is WHAT IS THAT CLUTCH SWITCH FOR?!? what is it's main function?? and also, will there be any drawbacks for driving around with the switch unplugged??
*phew* atleast the idle bouncing up and down while clutch pedal's down went away! i'm REAL HAPPY bout that
§ just added §
just read that the plug that i unplugged (yellow and black wire plug) is not the power for the switch. the yellow wire goes to the ECU, and the black is a ground.
the idle bumps up about 200-300 RPM's when i push in the clutch (which is way better than the idle bouncing btw)... now, can i get an explanation on that? why would the clutch pedal have an affect on idling?
§ just added § hmmm...
http://forum.teamfc3s.org/showthread...=clutch+switch
guess i should get a new one....
so pretty much unplugging the switch solved the problem. (thanks rotorman85!!!), but i am still kinda stumped
i have to push the clutch pedal down in order for the car to start, and by unplugging the clutch switch, i was assuming i didn't have to do that anymore, BUT i still do... so my question is WHAT IS THAT CLUTCH SWITCH FOR?!? what is it's main function?? and also, will there be any drawbacks for driving around with the switch unplugged??
*phew* atleast the idle bouncing up and down while clutch pedal's down went away! i'm REAL HAPPY bout that
§ just added §
just read that the plug that i unplugged (yellow and black wire plug) is not the power for the switch. the yellow wire goes to the ECU, and the black is a ground.
Last edited by ePH C freak; Mar 22, 2007 at 05:30 PM.
HAILERS
Joined: May 2001
Posts: 20,563
Likes: 27
From: FORT WORTH, TEXAS,USA
The clutch switch at the TOP of the pedal determines if the starter circuit is complete or not.
The bottom switch is the cruise control switch. It turns the cruise off, so to speak, when you hit the pedal and the cruise is engaged.
The bottom switch is the cruise control switch. It turns the cruise off, so to speak, when you hit the pedal and the cruise is engaged.
The ECU is supposed to raise the idle by 100-150rpm when you press the clutch in. This is supposed to make it easier to take off from a stop since there is very little torque at idle. Yours must have been overshooting that target and when it gets too high, it cuts back, goes too low and then the idle bounces again. I would suspect the IAC is sticking, and cleaning it should fix it.
Vince
Vince
Trending Topics
Passenger
Posts: n/a
From: So. CaL
sorry i haven't followed up on this thread.
project87 gxl: would you enlighten me a lil' on the "IAC"? i've never heard or ran into that term before. i did a search on it and i'm assuming it means "Idle Air Control Valve"? is it the ACV?? anyway, i'm willing to investigate that.
so far, the car is running nice. i'm almost certain that the only issue i have (which is a pest), is a vacuum leak.
on cold start, car idles around 2.3k~2.5k RPM, after 17 seconds, it drops down to about 1.8k~2k RPM and yet surges/fluctuates ANNOYINGLY. but after FULL WARM UP, the car purrs at a steady 1k RPM (which is the lowest i EVER had it idle).
i'm assuming that as the car gets warmer and warmer, the vacuum leak gets "weaker". does that make sense??
project87 gxl: would you enlighten me a lil' on the "IAC"? i've never heard or ran into that term before. i did a search on it and i'm assuming it means "Idle Air Control Valve"? is it the ACV?? anyway, i'm willing to investigate that.
so far, the car is running nice. i'm almost certain that the only issue i have (which is a pest), is a vacuum leak.
on cold start, car idles around 2.3k~2.5k RPM, after 17 seconds, it drops down to about 1.8k~2k RPM and yet surges/fluctuates ANNOYINGLY. but after FULL WARM UP, the car purrs at a steady 1k RPM (which is the lowest i EVER had it idle).
i'm assuming that as the car gets warmer and warmer, the vacuum leak gets "weaker". does that make sense??
HAILERS
Joined: May 2001
Posts: 20,563
Likes: 27
From: FORT WORTH, TEXAS,USA
http://wombat.sevarg.net/RX7/RX-7_Training_Manuals/
Download and read the FUEL AND EMISSIONS part. Around page fifty they describe the BAC. The BAC is the bypass air control that tries to maintain a idle under various conditions. Look carefully. I see no mention of the clutch switch when talking about idle speed. Maybe you can find it........somewhere. Ain't in the FSM nor the training manual in that link.
Download and read the FUEL AND EMISSIONS part. Around page fifty they describe the BAC. The BAC is the bypass air control that tries to maintain a idle under various conditions. Look carefully. I see no mention of the clutch switch when talking about idle speed. Maybe you can find it........somewhere. Ain't in the FSM nor the training manual in that link.
HAILERS
Joined: May 2001
Posts: 20,563
Likes: 27
From: FORT WORTH, TEXAS,USA
Originally Posted by HAILERS
http://wombat.sevarg.net/RX7/RX-7_Training_Manuals/
Download and read the FUEL AND EMISSIONS part. Around page fifty they describe the BAC. The BAC is the bypass air control that tries to maintain a idle under various conditions. Look carefully. I see no mention of the clutch switch when talking about idle speed. Maybe you can find it........somewhere. Ain't in the FSM nor the training manual in that link.
Download and read the FUEL AND EMISSIONS part. Around page fifty they describe the BAC. The BAC is the bypass air control that tries to maintain a idle under various conditions. Look carefully. I see no mention of the clutch switch when talking about idle speed. Maybe you can find it........somewhere. Ain't in the FSM nor the training manual in that link.
Junior Member
Joined: Mar 2008
Posts: 13
Likes: 0
From: Philadelphia
I had a fluctuating idle issue myself when my car was stopped and the clutch was engaged. I called a rotary specialist and he suggested the clutch switch might be bad. Turns out I had a broken spring in my clutch switch which is located behind the clutch pedal. All you have to do is unscrew the clutch switch from the pedal and open the switch using a flat screwdriver. Inspect the switch, clean it with alcohol and make sure the spring is in one piece. If not replace the spring and you should be fine. Or you can just purchase a new clutch switch- shouldn't be that expensive.
Also make sure your idle is @ 850 rpm in neutral after the car is warmed up (drive for 10 minutes). adjust idle screw at top of manifold with black rubber cap. Clockwise to idle down... and counter-clockwise to idle up.
My idle is PERFECT now!
Also make sure your idle is @ 850 rpm in neutral after the car is warmed up (drive for 10 minutes). adjust idle screw at top of manifold with black rubber cap. Clockwise to idle down... and counter-clockwise to idle up.
My idle is PERFECT now!
Joined: Sep 2005
Posts: 25,581
Likes: 136
From: Smiths Falls.(near Ottawa!.Mapquest IT!)
YOU are NOT the only guy that HAD this problem Marc..I Happened to Come across another Thread,and some guy did a Cleaning of that switch,and Presto!,No more Idle problems..I first Read it and thought "no Freakin way!..this guy Is Full of it!." but Since you have the Same problem,Then I now know it Can Happen!..look under Sec gen Specific..something Titles like.."surging idle,Bumpy idle..Etc"..STYX.
Thread
Thread Starter
Forum
Replies
Last Post
ncds_fc
New Member RX-7 Technical
1
Aug 15, 2015 10:06 AM
rkhanso
2nd Generation Specific (1986-1992)
1
Aug 13, 2015 11:40 AM
