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Smooth shifting not Smooth anymore

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Old Feb 4, 2009 | 08:02 PM
  #1  
DMoneyRX-7's Avatar
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Derek
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From: Treasure Coast, FL
Smooth shifting not Smooth anymore

About 2 or 3 weeks ago my shifting started getting annoying as its not smooth. When referring to smooth I'm saying...When I shift from any gear to another gear, the car almost bogs down. So when I shift from say 2nd to 3rd giving it a regular amount of acceleration and I let the clutch out completely the car slightly bogs and jumps about 2 times.

I was thinking that it was clutch related because it felt like the engagement point became higher up on the pedal travel. But now that I explained it I'm thinking that it could be my differential bushings.

Reason being, it doesn't happen all the time. Sometimes it can be smooth. But I'm thinking it is bogging or hesitating because the diff is not solid and therefore causes feedback in the driveline. Making it seem like it is bogging down.

I was also thinking that it might have something to do with fuel. Could it possibly be an injector or something?

Where should I start checking and how? That sounds really noobish but I need some help.
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Old Feb 4, 2009 | 09:07 PM
  #2  
apeiron
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Do a search for "dashpot" and read up.
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Old Feb 4, 2009 | 09:14 PM
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this also sounds like a symptom of an out of wack TPS sensor , whenever you reengage on the throttle after a gear change , iy you do it lightly and your TPS is not properly adjusted .. it will have this jerking effect on it ... but only happens at light throttle ( it may be possible that the TPS stopped transmiting Voltages correctly in the first stages ( partial opened throttle ) or simply needs an alignment for what ever reason

so check the TPS for correct voltage range , also check the dash pot nut and adjust it to cushion the throttle by screwing the dash pot 1 -2 threads at the time see if it changes .

start with dash op then go to TPS .. easier that way
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Old Feb 4, 2009 | 09:22 PM
  #4  
DMoneyRX-7's Avatar
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Derek
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My TPS is disconnected as I don't use it anymore.
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Old Feb 4, 2009 | 09:33 PM
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Derek
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From: Treasure Coast, FL
Last time I checked my dashpot the white plunger was sticking out. I'll check again. This makes sense though. Because when I shift I let off the gas which, if the dashpot is not working the rpms would go down and slow the car alot.
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Old Feb 4, 2009 | 11:46 PM
  #6  
Brent Dalton's Avatar
Sua Sponte
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Derrick,
Talk to Dan Chadwick. He can square you away on this. Are you sure your TPS is disconnected?
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Old Feb 5, 2009 | 12:00 AM
  #7  
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you rive with the TPS disconnected ???? y is that ?
btw TPS= throttle positioning sensor ... are you mistaking it with the .... IACV ( the other thing behind the intake minifold .. towards the firewall

this is the TPS :
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Old Feb 5, 2009 | 03:02 PM
  #8  
DMoneyRX-7's Avatar
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Derek
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From: Treasure Coast, FL
Derrick,
Talk to Dan Chadwick. He can square you away on this. Are you sure your TPS is disconnected?
Alright. I am about 80% sure.

you rive with the TPS disconnected ???? y is that ?
btw TPS= throttle positioning sensor ... are you mistaking it with the .... IACV ( the other thing behind the intake minifold .. towards the firewall
I am pretty sure it's disconnected. I'll check in a bit to make sure
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Old Feb 5, 2009 | 03:25 PM
  #9  
DaveW's Avatar
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Is it possible your secondary throttle plates are sticking? Check out this thread:

https://www.rx7club.com/showthread.p...lity+secondary
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Old Feb 5, 2009 | 04:43 PM
  #10  
1QWIK7's Avatar
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Sounds like a dashpot problem.

Try to accelerate in like 2nd gear to like 4k, then clutch in and put it to neutral and see how the rpm's drop.

If it drops fast, then its most probably the dashpot.
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