jerking when going highway speeds
08-18-2008, 09:22 PM
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c'mon
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jerking when going highway speeds
Basically when going highway speeds the car starts to jerk/hesitate when holding the speed limit. It seems like the bumps are causing the car to jerk also if im building boost the car will blow off when I hit a bump like I let off the gas even though I don't. This only occurs at highway speeds and in the city the car drives like a dream. Car is an 01 VW GTI.
08-18-2008, 09:40 PM
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Re: jerking when going highway speeds
At what throttle position does this happen? You may have some sort of part throttle mapping problem, and may need some more tuning. Torque loads are different depending on gear ratio, so it may not show up in lower gears at lower speeds.
08-18-2008, 09:44 PM
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Re: jerking when going highway speeds
just lightly holding throttle like 2800 rpms@60mph. I'm gonna clean my maf tomorrow and see if that helps the problem at all.
08-18-2008, 09:45 PM
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Re: jerking when going highway speeds
Try to replicate that throttle position in a different gear around town and see if you can spot any common behavior.
08-18-2008, 09:48 PM
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Re: jerking when going highway speeds
08-19-2008, 09:07 AM
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Re: jerking when going highway speeds
May be a loose coupler in the intake system, or some other type of intake leak. If you have an engine with a MAF, any leak that is between the MAF and the engine can cause glitches. Once you measure the airmass with the MAF, any air that is lost or gained can make glitches because the engine isn't getting what the ECU has already predicted.
There are other possibilities too, it's going to be something mechanical though probably because of the bumpy road stuff. Check that you don't have any cracked spark plugs, and that your plug wires are making proper (tight) contact and don't lose continuity when wiggled, etc.. This is going to be a fun thing to track down, make no mistake...
There are other possibilities too, it's going to be something mechanical though probably because of the bumpy road stuff. Check that you don't have any cracked spark plugs, and that your plug wires are making proper (tight) contact and don't lose continuity when wiggled, etc.. This is going to be a fun thing to track down, make no mistake...
08-19-2008, 09:24 AM
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Re: jerking when going highway speeds
May be a loose coupler in the intake system, or some other type of intake leak. If you have an engine with a MAF, any leak that is between the MAF and the engine can cause glitches. Once you measure the airmass with the MAF, any air that is lost or gained can make glitches because the engine isn't getting what the ECU has already predicted.
There are other possibilities too, it's going to be something mechanical though probably because of the bumpy road stuff. Check that you don't have any cracked spark plugs, and that your plug wires are making proper (tight) contact and don't lose continuity when wiggled, etc.. This is going to be a fun thing to track down, make no mistake...
There are other possibilities too, it's going to be something mechanical though probably because of the bumpy road stuff. Check that you don't have any cracked spark plugs, and that your plug wires are making proper (tight) contact and don't lose continuity when wiggled, etc.. This is going to be a fun thing to track down, make no mistake...
08-19-2008, 09:34 AM
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Re: jerking when going highway speeds
May be a loose coupler in the intake system, or some other type of intake leak. If you have an engine with a MAF, any leak that is between the MAF and the engine can cause glitches. Once you measure the airmass with the MAF, any air that is lost or gained can make glitches because the engine isn't getting what the ECU has already predicted.
There are other possibilities too, it's going to be something mechanical though probably because of the bumpy road stuff. Check that you don't have any cracked spark plugs, and that your plug wires are making proper (tight) contact and don't lose continuity when wiggled, etc.. This is going to be a fun thing to track down, make no mistake...
There are other possibilities too, it's going to be something mechanical though probably because of the bumpy road stuff. Check that you don't have any cracked spark plugs, and that your plug wires are making proper (tight) contact and don't lose continuity when wiggled, etc.. This is going to be a fun thing to track down, make no mistake...
08-19-2008, 09:40 AM
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