Bad, shaky idle.
10-19-2001, 06:21 PM
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Bad, shaky idle.
Hey guys, when I am just sitting in my car with it in neutral and the engine on, the car idles at about (what appears to be on the tach) 800 RPM. However, when I turn my headlights on, the RPM drops about 100 then goes back up,but when it goes down I can hear the engine lug down, and it gets shaky, then stays fairly shaky.. then if I turn my fog lights on, the RPM drops 100 or 200 then goes back up, but when it goes down I hear the engine lug down again and it gets even shakier.. (<--- Is that a word??) And sometimes it even does it when I have the lights on and press the brake pedal causing the taillights to light up.. any idea what's causing this? Someone told me I might need a bigger alternator, but for some reason I doubt that's what it is, hoping maybe some of you could help. Thanks in advance everyone! 
10-20-2001, 01:39 AM
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As I anticipated, however, when I leave my headlights on, the idle stays rough and shaky, but when I'm not idling, like when I'm driving, or if I even rev the engine to just over 1000 RPM, it feels just fine, until it drops back to idle and it's rough again.. 
10-20-2001, 10:40 AM
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These are my suggestions.
check your vacuum lines one or more might have fallen off. And how old is your battery it might be going bad thus making the alt work harder and this will also cause the rpm's to drop because the alt has to put more out to keep the battery charged up.
check your vacuum lines one or more might have fallen off. And how old is your battery it might be going bad thus making the alt work harder and this will also cause the rpm's to drop because the alt has to put more out to keep the battery charged up.
10-22-2001, 02:50 PM
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Ok there is two on the rubber elbow attached to the TB one going to a Bosch sensor and one going to the block (I beleive) but there are two ther one on the top of the elbow and one on the bottom. Then there is another one, start where the TB conects to intake manifold follow along the top of the manifold all the way over to the passanger side on the outside you will see a little house it almost looks like a wire and there ya go.
10-23-2001, 08:43 AM
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Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
What you are experiencing is normal. When you put electrical load on the system, the alt fires up to compensate, this lugs the engine down due to increased drag, till the ecu notices and compensates by rasing the idle again. If you shut the lights off, the revs will jump by 100 as the alt shuts off.
Don't worry too much about it, it is normal.
The car should idle at 800 RPM +/- 100 RPM, so you are right where it should be.
Don't worry too much about it, it is normal.
The car should idle at 800 RPM +/- 100 RPM, so you are right where it should be.