Blue Batmobile
Viper Owner
Hey guys, I've noticed this a few times. When I'm driving slow speeds say in 1st or 2nd gear and ease off the gas pedal, my car gets this jerking or bucking reaction. Any idea?
Bat™
Bat™
Jerking reaction when easing off the gas pedal in 1st or 2nd gear...
- Thread starter Blue Batmobile
- Start date
96GTS
Enthusiast
It's called "bucking" and mine does it too. I took it to a Viper tech, and of course I couldn't get the car to do it while he was in the car. He said it was common and nothing to worry about.
Blue Batmobile
Viper Owner
No engine mods yet. I'll have to check my rpms when this is happening.
Bat™
Bat™
Andrew/USPWR
Enthusiast
I think they all do that, especially when the engine is warming up. They are happier with a little more rpms.
Remember it’s a thoroughbreds and want to run
Remember it’s a thoroughbreds and want to run
ACR steve
Enthusiast
shift at a higher rpm ,sounds like you are shifting at too low a rpm which causes bucking
Saint_Spinner
Viper Owner
Ok...this is just a longshot (and by no means am I comparing the cars). I had the same problem in my twin-turbo Rx-7...low rpms, just light load and coasting at 5-10mph and all of a sudden the car would just start bucking.
Took it to Rotary specialist and he solved it with one wire...turned out it was a common thing with the Rx-7...grounding problems. He took a cable and screwed it onto the engine block (this case it was the rotary housing)and screwed the other end onto a body part (I think it was the firewall). He just sandpapered a bit of the paint off as to get a better connection.
This completely solved the issue.
Took it to Rotary specialist and he solved it with one wire...turned out it was a common thing with the Rx-7...grounding problems. He took a cable and screwed it onto the engine block (this case it was the rotary housing)and screwed the other end onto a body part (I think it was the firewall). He just sandpapered a bit of the paint off as to get a better connection.
This completely solved the issue.
Hi< Mike J here. U may consider this...if you have a light weight flywheel (aluminum) installed, then you can expect this kind of "feel" or bucking as you mentioned. In this case it would be attributed to intetia and rotating mass, that is with a stock iron flywheel the intertia that is generated eats up some of that energy and smooths out the transition in gearing at low speeds.
Something to think about.
best to ya, Mike
Something to think about.
best to ya, Mike
Dimitrios
Enthusiast
mine does it when the motor is cold and not warm enough.
Andrew/USPWR
Enthusiast
Took it to Rotary specialist and he solved it with one wire...turned out it was a common thing with the Rx-7...grounding problems. He took a cable and screwed it onto the engine block (this case it was the rotary housing)and screwed the other end onto a body part (I think it was the firewall). He just sandpapered a bit of the paint off as to get a better connection.
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My Viper tech ran that wire on my car. I guess it helped but it will still do it @ low RPM’s. I cured it by just keeping the RPM’s up.
Hi< Mike J here. U may consider this...if you have a light weight flywheel (aluminum) installed, then you can expect this kind of "feel" or bucking as you mentioned. In this case it would be attributed to intetia and rotating mass, that is with a stock iron flywheel the intertia that is generated eats up some of that energy and smooths out the transition in gearing at low speeds.
Something to think about.
best to ya, Mike
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I also removed my aluminum fly wheel which did help, but not a complete cure.
I guess to easiest solution would be to never ease off of the gas
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My Viper tech ran that wire on my car. I guess it helped but it will still do it @ low RPM’s. I cured it by just keeping the RPM’s up.
Hi< Mike J here. U may consider this...if you have a light weight flywheel (aluminum) installed, then you can expect this kind of "feel" or bucking as you mentioned. In this case it would be attributed to intetia and rotating mass, that is with a stock iron flywheel the intertia that is generated eats up some of that energy and smooths out the transition in gearing at low speeds.
Something to think about.
best to ya, Mike
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I also removed my aluminum fly wheel which did help, but not a complete cure.
I guess to easiest solution would be to never ease off of the gas
2000gtsgsxr1000
Enthusiast
They all do it.
Blue Batmobile
Viper Owner
My thinking may because I haven't driven the car in a few days and just needed to get warmed up a bit.
Bat™
Bat™
AviP
Enthusiast
In my case, it's a parking lot thing. Slow speeds. Blipping the throttle to 2000 rpm and backing off will do it. It's the torque monster under the hood.
And don't listen to ACR Steve, he'll have you doing 60mph in your driveway.
And don't listen to ACR Steve, he'll have you doing 60mph in your driveway.
Cal Cobra
Viper Owner
Easy fix, give it more gas!
Mine does it, but only when the engine is cold, seems to be normal is the general consensus. I adjusted the throttle bodies, and it was better, but still present when cold.
Cal
Mine does it, but only when the engine is cold, seems to be normal is the general consensus. I adjusted the throttle bodies, and it was better, but still present when cold.
Cal
Kevin ACR
Enthusiast
There is a throttle synchronization in the how to for gen I , do the Gen II have the ability to synchronize the throttle bodies via the shaft? Can it come out of sync? Just a thought.
peakcompletions
Viper Owner
I had David Weaver install an AEM on both of my GTS cars and.. no more bucking... tuned it out with the computer... plus more power.
The only thing I didn't like about the install of the AEM on my Venom 650 R was it idled so dang smooth. I got Justin and DW to play with it and now it idles and lopes rough again. Love it.
The only thing I didn't like about the install of the AEM on my Venom 650 R was it idled so dang smooth. I got Justin and DW to play with it and now it idles and lopes rough again. Love it.
twinturbo3150
Enthusiast
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will a new AEM improve HP&TQ on a new 06 coupe and estimate HP gains. thanks
MacManInfi
Enthusiast
I see that the throttlebodies on the GenII's are adjustable via a little screw and locking nut on the passanger side throttlebody. No idea how you'd sync them up though. I also don't know if they can come out of sync. I see that mine has a little yellow dab of paint on the screw and not to mark where they were aligned.
Mine bucks a lot at parking lot speeds, warm or cold. The thing I wind up doing is shifting to the next gear to drop the rpms and keep a load on the motor and drivetrain. Still seems like it shouldn't do that though.
It is not normal that a modern injection engin bucks. The PCM should adjust fuel according to the temperature.
As Cal Cobra & Peak Completitions points out the problem can be fixed. When cold, the Viper engin runs too lean. It is related to a bug in the PCM. When I lean out my AFR for highway riding I can't even start my engin when it is cold ! The engin would run 19-22 AFR at the startup during 2-3 minutes.
If I don't lean and let the PCM manage my fuel, still the engin runs in the 16AFR. Usually a cold engin should run in the 13-14AFR. Then once the engin gets hot everything works much better but still there is a bug.
Sean is working on a fix that Dodge didn't want to do.
As Cal Cobra & Peak Completitions points out the problem can be fixed. When cold, the Viper engin runs too lean. It is related to a bug in the PCM. When I lean out my AFR for highway riding I can't even start my engin when it is cold ! The engin would run 19-22 AFR at the startup during 2-3 minutes.
If I don't lean and let the PCM manage my fuel, still the engin runs in the 16AFR. Usually a cold engin should run in the 13-14AFR. Then once the engin gets hot everything works much better but still there is a bug.
Sean is working on a fix that Dodge didn't want to do.
joe117
Enthusiast
In more than a few cases this is caused by the driver getting bounced back slightly when the car accelerates slightly.
The drivers foot comes up off the gas pedal slightly and the car slows, the foot presses a little more as the driver moves forward due to the slowing.....
The point is, you can bounce a little and feed back that bounce into the gas pedal.
In an aircraft, a pilot can get into this kind of situation where a control input causes a reaction, then the correction causes a reaction, then the syndrome increases in magnitude and it get's worse and worse.
Try this.
Make sure you are strapped in tight with your butt planted firmly in the seat.
Press the right side of your foot against the carpet to the right of the gas pedal. This will tend to keep your foot a little more steady in place.
Feed in more gas pedal by turning your foot slightly so the left side is pressing down.
Kind of roll your foot.
When the engine gets a little throttle and lurches forward, don't let it move your foot off the pedal, not even a little.
I'll bet that if you can keep the accel, decel, gas pedal syndrome from happening, your car will not buck.
The drivers foot comes up off the gas pedal slightly and the car slows, the foot presses a little more as the driver moves forward due to the slowing.....
The point is, you can bounce a little and feed back that bounce into the gas pedal.
In an aircraft, a pilot can get into this kind of situation where a control input causes a reaction, then the correction causes a reaction, then the syndrome increases in magnitude and it get's worse and worse.
Try this.
Make sure you are strapped in tight with your butt planted firmly in the seat.
Press the right side of your foot against the carpet to the right of the gas pedal. This will tend to keep your foot a little more steady in place.
Feed in more gas pedal by turning your foot slightly so the left side is pressing down.
Kind of roll your foot.
When the engine gets a little throttle and lurches forward, don't let it move your foot off the pedal, not even a little.
I'll bet that if you can keep the accel, decel, gas pedal syndrome from happening, your car will not buck.
Blue Batmobile
Viper Owner
I've tried putting my right foor against the side and easing up ever so slowly, still bucks. In my case, I'm really leaning towards the possibilty that the engine was not warmed up yet. Then again, I could be wrong.
Bat™
Bat™
94RT10Ohio
Enthusiast
In my case, it's a parking lot thing. Slow speeds. Blipping the throttle to 2000 rpm and backing off will do it. It's the torque monster under the hood.
And don't listen to ACR Steve, he'll have you doing 60mph in your driveway.
Agreed. This happened to me 1 time. Cold engine, hit the gas slightly leaving work, let off and the ride was on. Pushed in the cluch to get it to stop. No big deal, I just learned if I am going to hit the gas on a cold engine (yea, not a good idea) to keep my foot in it and keep the RPMs up.
Blue Batmobile
Viper Owner
got it.
Bat™
MacManInfi
Enthusiast
BTW, I synced my TB's on Saturday. Drove it Sunday and to work today. No more bucking.
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