Odd downshifting operation
#1
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Vehicle: 2001 Hyundai Tiburon
Odd downshifting operation
When driving my 2001 tiburon (little newer than 97' RD1)
Problem:
Downshifting seems pointless to me in 2nd and 3rd gear, cause all the engine seems to do is buck back and fourth very sporadically in a controlled manner. No decrease in speed is really benficial. It seems now it is a severe mechanic disfunction.
My thoughts and outcome:
Since I bought it used, maybe it was revved really high (previously by its owner) and relied on downshifting at high RPM to slow down more for some reason In my head only am I thinking of that, so try to bounce back off that thought. Possibly overspinning bearings and ruining internal components?
The downshifting in this manual car acts retarded like it does not know what it is doing. And just rolls along..
The car runs fine besides this?
Problem:
Downshifting seems pointless to me in 2nd and 3rd gear, cause all the engine seems to do is buck back and fourth very sporadically in a controlled manner. No decrease in speed is really benficial. It seems now it is a severe mechanic disfunction.
My thoughts and outcome:
Since I bought it used, maybe it was revved really high (previously by its owner) and relied on downshifting at high RPM to slow down more for some reason In my head only am I thinking of that, so try to bounce back off that thought. Possibly overspinning bearings and ruining internal components?
The downshifting in this manual car acts retarded like it does not know what it is doing. And just rolls along..
The car runs fine besides this?
#3
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Trying very hard to see a point to this thread . . .
. . . are you saying your engine bounces a lot when you downshift, and it doesn't slow the car as much as you think it should?
If the engine bounces a lot and you haven't replaced the roll stops (engine mounts on the bottom) they are almost certainly shot. If it isn't slowing the car like it should, it could be due to low compression (old engine) or weak coupling (torque converter = normal). Check the roll stops first.
. . . are you saying your engine bounces a lot when you downshift, and it doesn't slow the car as much as you think it should?
If the engine bounces a lot and you haven't replaced the roll stops (engine mounts on the bottom) they are almost certainly shot. If it isn't slowing the car like it should, it could be due to low compression (old engine) or weak coupling (torque converter = normal). Check the roll stops first.
#4
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Vehicle: 2002 hyundai accent
Had the same problems. wore out the roll stops doing 50mph down old dirt/gravel roads.
buy a tube of window weld, seach the forum for the how to, then fill the motor mounts. the throttle response will improve but be warned, at idle your soft drink will go flat in about 20 seconds.
#5
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Vehicle: 2001 Hyundai Tiburon
Motor mounts seem OK.
The car has 60,000 mi on the engine..
I don't get how a rubber roll stopper would get ruiend they're made of rubber, ive saw cars with over 150,000 mi that had no roll stop probs
The car has 60,000 mi on the engine..
I don't get how a rubber roll stopper would get ruiend they're made of rubber, ive saw cars with over 150,000 mi that had no roll stop probs
#6
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Vehicle: 2002 hyundai accent
-this has been my only FWD car but from my understanding its common. pop the hood and have someone hold the brake down, and simultaneously push the accelerator down almost enough to break the tires loose. if the engine/tranny moves very much then your roll stops are worn. sometimes when theyre worn its not visually obvious.
-mine where worn out somewhere around 30-50k
-if its not the roll stops then I dont know what it is.
#8
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The lower motor mounts are the roll stops in question.
They are rubber parts. Rubber loses its elasticity with time and heat, of both of which your roll stops have had plenty through the years. They get old, they get hard, they continue to be pounded by the engine trying to move, and they fall apart. If they don't look new, they need replacement. ANY cracks at this age mean they are shot.
Unless you just live for danger, try gunning the gas with the transaxle in NEUTRAL. Holding the brake not required. If the engine flops, it probably needs roll stops.
Filling them with a soft elastomer only slightly increases NVH over good stock mounts. My car actually drove smoother overall, because the engine stopped leaping all over the place.
They are rubber parts. Rubber loses its elasticity with time and heat, of both of which your roll stops have had plenty through the years. They get old, they get hard, they continue to be pounded by the engine trying to move, and they fall apart. If they don't look new, they need replacement. ANY cracks at this age mean they are shot.
Unless you just live for danger, try gunning the gas with the transaxle in NEUTRAL. Holding the brake not required. If the engine flops, it probably needs roll stops.
Filling them with a soft elastomer only slightly increases NVH over good stock mounts. My car actually drove smoother overall, because the engine stopped leaping all over the place.