Gas pedal: How to reduce its back pressure?
#1
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This has been an issue since I have the car, but I have never gotten a clear solution to the issue:
The gas pedal on my car has way too much back pressure. After driving the car for a while I get problems with my sciatic nerve and sometimes even the hip joint. I don't think I will be taking this beast on a long trip before I found a way to reduce that pressure to something more normal...
What causes the strong back pressure? Is it a spring in the throttle cage, or under the intake? Where and how can this be adjusted - does the Intake have to come off to do this?
The gas pedal on my car has way too much back pressure. After driving the car for a while I get problems with my sciatic nerve and sometimes even the hip joint. I don't think I will be taking this beast on a long trip before I found a way to reduce that pressure to something more normal...
What causes the strong back pressure? Is it a spring in the throttle cage, or under the intake? Where and how can this be adjusted - does the Intake have to come off to do this?
#2
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Nicole:
You can try some silicone lubricant shot down the cable and check of the pivot points for binding. However, the coil spring on the throttle plate, unfortunately hidden under the intake, is the biggest factor. It can be loosened a turn...after you remove the intake.
You can try some silicone lubricant shot down the cable and check of the pivot points for binding. However, the coil spring on the throttle plate, unfortunately hidden under the intake, is the biggest factor. It can be loosened a turn...after you remove the intake.
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Originally Posted by Nicole
This has been an issue since I have the car, but I have never gotten a clear solution to the issue:
The gas pedal on my car has way too much back pressure. After driving the car for a while I get problems with my sciatic nerve and sometimes even the hip joint. I don't think I will be taking this beast on a long trip before I found a way to reduce that pressure to something more normal...
What causes the strong back pressure? Is it a spring in the throttle cage, or under the intake? Where and how can this be adjusted - does the Intake have to come off to do this?
The gas pedal on my car has way too much back pressure. After driving the car for a while I get problems with my sciatic nerve and sometimes even the hip joint. I don't think I will be taking this beast on a long trip before I found a way to reduce that pressure to something more normal...
What causes the strong back pressure? Is it a spring in the throttle cage, or under the intake? Where and how can this be adjusted - does the Intake have to come off to do this?
#4
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I was having this problem with my 79. It turned out to be that the cable was fraying inside the housing. I was in denial at first until I looked at the junction where the cable goes out from the pedal to the housing. I fixed mine using the steel cable from a mountain bike brake and some ferrals.
I, too have the problem with the siatic nerve but mine comes from the famous L5 disk in my lower back.
Good Luck
I, too have the problem with the siatic nerve but mine comes from the famous L5 disk in my lower back.
Good Luck
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#6
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Sorry to hear about your discomfort.
The easiest way to reduce the pedal force with your automatic, is to slacken the Bowden control pressure cable at the spherical head located at cable console on the side of the intake manifold. It's easy to loosen, test, and restore.
WSM calls for taking any slack out of the cable, but some slack is permissible without significant loss/change of transmission shift performance.
I like mine looser on my 90' S4 than WSM recommended for two reasons. First the pedal pressure is lighter, and second, is the cable is less likely to stretch or bind with the cable guide.
The easiest way to reduce the pedal force with your automatic, is to slacken the Bowden control pressure cable at the spherical head located at cable console on the side of the intake manifold. It's easy to loosen, test, and restore.
WSM calls for taking any slack out of the cable, but some slack is permissible without significant loss/change of transmission shift performance.
I like mine looser on my 90' S4 than WSM recommended for two reasons. First the pedal pressure is lighter, and second, is the cable is less likely to stretch or bind with the cable guide.
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#11
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My "long trip" solution is the electronic version of the Anders' method. I use the 'electric brick', actuated by the little stalk on the column, to unload the back-pressure on the right foot. It also helps me avoid the jail time that might happen as that same foot falls asleep and droops towards the floor.
Someone needs to configure an interface between the V1 and the electric brick.
Someone needs to configure an interface between the V1 and the electric brick.
#12
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Nicole,
Since the S4 have the throttle linkage on the side of the intake, I would suggest to install a simple coil spring that would aid pulling the throttle linkage open. Just a simple spring that mearly eases the throttle operation.
Since the S4 have the throttle linkage on the side of the intake, I would suggest to install a simple coil spring that would aid pulling the throttle linkage open. Just a simple spring that mearly eases the throttle operation.
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Originally Posted by Imo000
Nicole,
Since the S4 have the throttle linkage on the side of the intake, I would suggest to install a simple coil spring that would aid pulling the throttle linkage open. Just a simple spring that mearly eases the throttle operation.
Since the S4 have the throttle linkage on the side of the intake, I would suggest to install a simple coil spring that would aid pulling the throttle linkage open. Just a simple spring that mearly eases the throttle operation.
I respectfully disagree.
In the event of any failuire of the main spring, the 'new' spring will cause the throttle to go to full-open. This could cause a problem, or worse!
"Modern" cars come with two return springs, to make sure that failure of one spring doesn't cause a problem. Each spring needs to be able to pull the throttle closed in spite of any possible friction in the linkages and cables. As we experiment with taking a turn out of the throttle-plate spring, for instance, keep in mind that it still has to be able to hold the plate hard against the stop when released, without any assistance from other springs.
#15
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Nicole - I've driven your car and I don't recall it having heavy throttle pressure any more than my car. We can lube the cable, check over the pedal and linkage, make sure there are no kinks, but after that, you may just need to use the cruise control on those long drives, as antithetical as that is to your driving style.