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  #1  
Old 03-07-2003, 11:53 AM
robj213 robj213 is offline
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Found out a new thing about my car

When I was straightening my wheel out after parking today I noticed that the RPM drops when you turn the steering wheel when the engine is idling! When idling my engine is about 700 RPM, and if I turn the steering wheel a lil to either direction the RPM drops to about 500 then bounce back up!

Anybody else notice this?
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  #2  
Old 03-07-2003, 11:57 AM
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The HACK The HACK is offline
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If you have a stick shift, you can press the clutch pedal repeatedly in neutral and watch your RPM fluctuate between 650-750...And if you catch it on the right oscillation you can actually cause the car to STALL by just pumping the clutch pedal at the right frequency.

I think what's going on is the power steering pump is drawing power from the alternator, thus the alternator has to work harder...And where does the alternator's power come from? The engine. And what happens when power is drawn from the engine (resistence in the crank)? The RPM dips.

I've noticed this in almost all the cars I've ever driven and owned...Some more drastic than others, but all three of my BMWs did this.
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  #3  
Old 03-07-2003, 12:14 PM
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Kaz Kaz is offline
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Um... We don't have electric PS pumps. That's whats in the MINI and the new Accord. We have conventional mechanical PS pumps, but they also fall into the direct engine load category, so the RPMs fluctuate for the same reason.

This is with any accessory drive that turns on and off, like the AC compressor.
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  #4  
Old 03-07-2003, 12:26 PM
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The HACK The HACK is offline
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Um...I knew that. Yeah.

Thanks Kaz for pointing out the error in my post.
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"Bench racing" about track times driven by professionals are like a bunch of nerds arguing which Princess Leia is hotter, the slave Leia or the no-bra jail-bait Leia. No matter how compelling your argument is, the plain and simple fact is, none of you will EVER get to hit that.
  #5  
Old 03-07-2003, 12:55 PM
tgravo2 tgravo2 is offline
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It's funny, cause I used to have a 98 4 cylinder 5 spd mazda truck back in 98 and if I would turn my wheel all the way while just sitting there, my rpms would drop to about 100 for just a second, it would almost stall then it would go right back up to 650, it was wierd that it took so much out of the engine just to do that.
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  #6  
Old 03-07-2003, 01:19 PM
robj213 robj213 is offline
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Ahhh.. good explanation. Thanks
  #7  
Old 03-07-2003, 08:29 PM
visor visor is offline
 
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Re: Found out a new thing about my car

Quote:
Originally posted by robj213
When I was straightening my wheel out after parking today I noticed that the RPM drops when you turn the steering wheel when the engine is idling! When idling my engine is about 700 RPM, and if I turn the steering wheel a lil to either direction the RPM drops to about 500 then bounce back up!

Anybody else notice this?
This effect is very noticeable when trying to back out of a tight parking spot with the steering fully cranked one way. In the first 2 months of owning this car, I must have stalled the engine half a dozen times while doing this.
  #8  
Old 03-07-2003, 11:13 PM
robj213 robj213 is offline
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Quote:
This effect is very noticeable when trying to back out of a tight parking spot with the steering fully cranked one way. In the first 2 months of owning this car, I must have stalled the engine half a dozen times while doing this.
Wow, you stalled your car by turning the wheel? I haven't tried turning the steering fully toward one way yet, but that sucks that the engine would stall if you turn it all the way!
  #9  
Old 03-07-2003, 11:16 PM
visor visor is offline
 
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No, you misread me.
What I mean is while *backing* out with gas and half clutch and wheel fully turned...
You need to apply a little more gas when doing this than when backing out straight...

Last edited by visor; 03-07-2003 at 11:21 PM.
  #10  
Old 03-08-2003, 02:15 PM
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gek330i gek330i is offline
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Re: Found out a new thing about my car

Quote:
Originally posted by robj213
When I was straightening my wheel out after parking today I noticed that the RPM drops when you turn the steering wheel when the engine is idling! When idling my engine is about 700 RPM, and if I turn the steering wheel a lil to either direction the RPM drops to about 500 then bounce back up!

Anybody else notice this?
I thought I was the only one.
My car does exactly the same thing you have described.
Thanks for bringing it up!
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  #11  
Old 03-08-2003, 06:20 PM
smoke smoke is offline
 
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so i guess this is a normal thing.
  #12  
Old 03-25-2018, 02:33 PM
jimmy_rock jimmy_rock is offline
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Quote:
Originally Posted by robj213 View Post
When I was straightening my wheel out after parking today I noticed that the RPM drops when you turn the steering wheel when the engine is idling! When idling my engine is about 700 RPM, and if I turn the steering wheel a lil to either direction the RPM drops to about 500 then bounce back up!

Anybody else notice this?
My car does this while backing out with steering wheel being turned, rpm drops significantly and some time stalls if AC is on. Mine is automatic.
  #13  
Old 03-25-2018, 03:27 PM
Underwurlde Underwurlde is offline
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Wow!!!! Resurrection of a 15 year old tread. Is that a record ??? Lol....
 

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