Slightly rougher idle
#1
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Slightly rougher idle
The idle on my 3.6 seems a little rough, The tach is rock steady but it just seems a tad rougher, Like the old passenger seat is moving a little more
Would a cleaning of the MAF be in order?
Otherwise car feels great!
Would a cleaning of the MAF be in order?
Otherwise car feels great!
#2
Mine had a lumpy idle when I first bought it, and now it doesn't. I can't pinpoint what fixed it, but here's what I did over the first couple of service visits:
- New fuel filter.
- Throttle body service.
- Motorvac the fuel system.
- New plugs.
Runs like a champ.
- New fuel filter.
- Throttle body service.
- Motorvac the fuel system.
- New plugs.
Runs like a champ.
#3
How many miles when you did this?
I got that going on as well. Runs like dream but seems to bounce just a little bit at idle
I got 13K so I was not even thinking plugs, filter, etc...
Maybe I am being just to critical, I am somewhat of a perfectionist
I got that going on as well. Runs like dream but seems to bounce just a little bit at idle
I got 13K so I was not even thinking plugs, filter, etc...
Maybe I am being just to critical, I am somewhat of a perfectionist
Last edited by ls911; 04-10-2008 at 02:57 AM.
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#8
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Throttle body clean is quick and cheap, I'd start there.
http://www.renntech.org/forums/index...howtopic=15413
http://euroautoforums.com/forums/ind...showtopic=1351
http://www.popularmechanics.com/how_...e/1272341.html
http://www.renntech.org/forums/index...howtopic=15413
http://euroautoforums.com/forums/ind...showtopic=1351
http://www.popularmechanics.com/how_...e/1272341.html
#9
Race Director
MAF as others said, but why is MAF dirty. I cleaned one after 80,000+ miles...
I've got nearly 80,000 miles on the current MAF in my car and haven't had it out to clean it once. Running stock air intake and filter too.
For some model year vehicles, a variable cam timing selenoid could fail and the symptom was a lumpy idle. Don't know what your car's year is, if it has the electric variable cam timing selenoid, but if it does, and if MAF cleaning or other potential solutions don't help...
Sincerely,
Macster.
#10
macster, what years had the electric variable cam thing? I have had a idle issue in past. I cleaned the MAF, ICV and throttle body with some small success, but still feel vibration intermittently. My next thing was to replace fuel filter at next oil change, but perhaps that cam thing is issue. What kind of cash is the repair?
#12
Banned
isn't this vibration thing considered normal?
what's tough to gauge here is we're trying to prescribe something to something where we don't have any quantitative figures, just subjective observations about a seat moving more than usual.
then people read this and they're like oh man my seats vibrating, i need to go do x and y as i read on rennlist... what i notice is, the seat sometimes vibrates more, sometimes it doesn't vibrate at all. depends on temp, cold start or strip mall visit, etc.
i'm not so sure we're going to come to any sort of logical, salient conclusion here. if the vibration makes your voice sound like you're talking into a whirring fan... then consider a real looksy.
what's tough to gauge here is we're trying to prescribe something to something where we don't have any quantitative figures, just subjective observations about a seat moving more than usual.
then people read this and they're like oh man my seats vibrating, i need to go do x and y as i read on rennlist... what i notice is, the seat sometimes vibrates more, sometimes it doesn't vibrate at all. depends on temp, cold start or strip mall visit, etc.
i'm not so sure we're going to come to any sort of logical, salient conclusion here. if the vibration makes your voice sound like you're talking into a whirring fan... then consider a real looksy.
#13
Race Car
What monitors engine idle and regulates idle airflow?
I remember that when I placed a screwdriver on the butterfly in the throttle body (2000) I could feel the butterfly constantly moving back and forth. What tells the butterfly how much to open for idle?
On the 99's, the idle control valve or idle air bypass valve directed air around the butterfly, what tells the ICV or IABV to open or close at idle?
#14
Drifting
What monitors engine idle and regulates idle airflow?
I remember that when I placed a screwdriver on the butterfly in the throttle body (2000) I could feel the butterfly constantly moving back and forth. What tells the butterfly how much to open for idle?
On the 99's, the idle control valve or idle air bypass valve directed air around the butterfly, what tells the ICV or IABV to open or close at idle?
I remember that when I placed a screwdriver on the butterfly in the throttle body (2000) I could feel the butterfly constantly moving back and forth. What tells the butterfly how much to open for idle?
On the 99's, the idle control valve or idle air bypass valve directed air around the butterfly, what tells the ICV or IABV to open or close at idle?
"The throttle position is determined via a potentiometer fitted at the throttle valve. The DME control unit supplies the potentiometer with a regulated voltage (5 V). Depending on the potentiometer position (throttle opening angle), a higher or lower drop in voltage occurs at the potentiometer. The DME control unit uses the voltage drop and the corresponding current flow to determine the smallest opening angle for the throttle. This angle is defined as the idle speed position."
#15
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The DME is monitoring engine RPMs and adjusting air intake (either with the stepper motor throttle or the ICV in the case of the mechanical throttle) in order to maintain the idle RPM setting.