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

bsupra

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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

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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

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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
 

f00g00

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I had a dead spot on my tps that caused that issue when I had a 7MGE.
 

bsupra

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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

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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

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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.
 

bsupra

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Thanks for following up, that's some commitment almost five years later!
LOL... Yeah, I stopped working on it and just tried to ease up on the throttle when releasing it...

Until one day, youtube posted a recommended video about dashpot's lol. Sure enough, the screw stop was barely touching the screw stop when I checked it. After I justed it, issue was gone almost instantly.