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RPM surge!! *VIDEO*

Old Dec 16, 2010 | 01:05 AM
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Exclamation RPM surge!! *VIDEO*

Ok so a few months ago I was at a red light and my RPMs starting rising slowly and hovering around 3k rpm. The problem happened once more after that about a month ago. Today as I was getting home, it was happening again. This time however, I got it on film. Captured the sequence on my iPhones camera.

Basically, the RPMs rise and hover even though I am not applying any pressure what so ever on the gas pedal. This happens when the car is in neutral. I have a 6MT by the way. You will notice in the video that when I pull back on the gas pedal the RPMs drop to idle. I do put some pressure pulling back on it, but the pedal itself does not move one bit. Never really noticed if this happens while I am driving since I am constantly shifting gears and getting on and off the gas and what not, but it may be a cause for concern.

Here is the video:

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Old Dec 16, 2010 | 01:15 AM
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Dam that's weird! That happened to my chevy but forgot what the problem was, maybe the computer?
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Old Dec 16, 2010 | 01:21 AM
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Throttle position sensor going bad? I know with my uprev i can see the foot pedal position and throttle position. wonder if there is a way to connect to the obd port to monitor that.

I know my max i reset the throttle position sensor a few times. I never done it on the G or know if it can be done
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Old Dec 16, 2010 | 01:22 AM
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I think it might be something related with a censor. I mean the rpms rise and fall without any interaction with the gas pedal. Which is what makes it even weirder.
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Old Dec 16, 2010 | 11:12 AM
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My RPMs act weird when starting the car cold but once warmed up it's fine. You're obviously warmed up already (can see your temp gauge). Take that video to the dealer and get it checked out.
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Old Dec 16, 2010 | 11:16 AM
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Got the AC or any other accessories on (even seat warmers)?
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Old Dec 16, 2010 | 11:18 AM
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i actually have a pretty similar problem too...but i keep my car outside, and here in philly it gets to like 10 degrees in the morning and i see that mine idles on its own up to 2,000 rpms. but i think it's the weather because i took it to the dealership and they said there was nothing wrong with my sensors or anything like that...definitely would like to know if you have a resolution to that.
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Old Dec 16, 2010 | 12:07 PM
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My car was already warm when the issue started happening. When it initially happened a few months back the weather wasn't cold at all. The A/C was off, seat warmer was on, ventilation was on (set to defrost with A/C off), radio was on listening to my iPod...
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Old Dec 16, 2010 | 01:11 PM
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Originally Posted by Gee37S
My car was already warm when the issue started happening. When it initially happened a few months back the weather wasn't cold at all. The A/C was off, seat warmer was on, ventilation was on (set to defrost with A/C off), radio was on listening to my iPod...
very interesting....did you take it to the dealership?
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Old Dec 16, 2010 | 01:23 PM
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Looks like a throttle body problem or an o2 sensor is flaking.

You may want to check and make sure there aren't any obstructions in the intakes. (check the filters)
Could be spark plug issues too. Pull them and make sure.

Usually a car will spike up the rpms because it thinks it's going to stall.
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Old Dec 16, 2010 | 02:01 PM
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I have the R2C intakes I'll check that out. I'm pretty sure the first time I had this issue I was still on stock intakes. I'll have a look at them and the spark plugs too. I'll show the vid to the dealership and see what they say...
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Old Dec 16, 2010 | 11:16 PM
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From: Kuwait
See if you have any codes with Uprev cipher or a scanner. I would also check the operation of the TPS.
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Old Dec 17, 2010 | 07:12 AM
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Originally Posted by Gee37S
My car was already warm when the issue started happening. When it initially happened a few months back the weather wasn't cold at all. The A/C was off, seat warmer was on, ventilation was on (set to defrost with A/C off), radio was on listening to my iPod...

Very interesting....what was playing on the Ipod at the time?

Remember that this could also be VVTL related since at lower RPM and load conditions the ecu controls engine speed by valve lift as well as throttle angle...
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Old Dec 17, 2010 | 09:15 AM
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I cleaned my throttle bodies, as many do without problems but a similar occurence happened to me. High idle, and rpms would jump up to 1500-2000 while in idle when the car was warm. A simple throttle position relearn fixed it and the surge is gone and my idle is back down to 600-650 or so.
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Old Dec 17, 2010 | 10:33 AM
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Suppose it could be an Evac leak too.

Try unplugging the battery for 5 minutes. Should make the ecu reset and relearn, works for most cars.
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