Supra Jerks when stepping/letting go of gas...

bsupra

Member
Oct 1, 2006
140
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16
California
I previously own a 89 supra turbo. I remember every time I let go of the gas, it has a smooth deceleration.. On my 91 turbo, every time I let go or step of the gas, there is jerk fwd/back. I checked timing and TPS and they are pretty much in spec.....Any suggestions? Thanks
 

suprarx7nut

YotaMD.com author
Nov 10, 2006
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Arizona
www.supramania.com
Agreed with the mounts. Engine mounts can be completely torn and non-functional, but can look fine. When I've pulled engines on high mileage cars they've been consistently ripped or torn, but I didn't know it until I started lifting the engine.

I should really get around to replacing my trans mount...
 

MkiiiAllDay

New Member
Jul 19, 2013
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orange, CA
Is the jerking intense like it could be motor? If not it could be tans and diff related if it's slight Cuz i get a slight jerking in low gears, but that's do to diff backlash
 

bsupra

Member
Oct 1, 2006
140
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California
MkiiiAllDay;2066198 said:
Is the jerking intense like it could be motor? If not it could be tans and diff related if it's slight Cuz i get a slight jerking in low gears, but that's do to diff backlash

It feels like somebody just bump your rear bumper/ front bumper when you step/let go of gas pedal....
 

bsupra

Member
Oct 1, 2006
140
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16
California
suprarx7nut;2065995 said:
Agreed with the mounts. Engine mounts can be completely torn and non-functional, but can look fine. When I've pulled engines on high mileage cars they've been consistently ripped or torn, but I didn't know it until I started lifting the engine.

I should really get around to replacing my trans mount...

I have checked the engine mounts... Both sides look good physically and there is a small amount of tilt when I rev the engine....

I think you are right... It maybe the transmission mount... I can here a clunk when I every time the car jerks when I step/let go of the gas pedal. I will try checking the transmission mounts this weekend.
 

f00g00

Supramania Contributor
Jul 2, 2007
586
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Kuwait
I forgot to mention that when my car had the same problem the jerking ended up breaking my rear subframe.
It was probably the most power my NA had. If you have another TPS by all means try it.
I was lucky enough to find a rear subframe here in Kuwait at the junkyard at Amghara. Now there are 0 Supras in the yards since they had the yards moved to the middle of nowhere and there are maybe a dozen MKIII's on the road.