Weird "clunk" when in gear and off the throttle
Thread Starter
Joined: Nov 2012
Posts: 672
Likes: 16
From: Michigan
Car: 1988 IROC-Z/G92
Engine: 5.0
Transmission: T-5
Axle/Gears: BW 3.45 Eaton Truetrac
Weird "clunk" when in gear and off the throttle
Hello,
Curious situation here, prominently I notice this in 5th gear, however I would have to check again for the other gears.
If I am coasting, about 30 seconds after letting my foot off the gas, the car will sort of "surge" or "jerk" a bit as the engine speed is slowing down.
Only happens when in gear and coasting.
I have a tunnel mounted torque arm at the moment.
Any idea what the problem could be here?
Curious situation here, prominently I notice this in 5th gear, however I would have to check again for the other gears.
If I am coasting, about 30 seconds after letting my foot off the gas, the car will sort of "surge" or "jerk" a bit as the engine speed is slowing down.
Only happens when in gear and coasting.
I have a tunnel mounted torque arm at the moment.
Any idea what the problem could be here?
Thread Starter
Joined: Nov 2012
Posts: 672
Likes: 16
From: Michigan
Car: 1988 IROC-Z/G92
Engine: 5.0
Transmission: T-5
Axle/Gears: BW 3.45 Eaton Truetrac
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Weird "clunk" when in gear and off the throttle
DFCO (decel fuel cut off) is just that. On long decels from speed the ECM cuts the fuel to the engine. Then as the vehicle slows along with the engine slowing fuel is resumed. It is at this point the drive line can jerk. More so on a modified vehicle.
RBob.
RBob.
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From: 212 is up in this Bit@#
Car: Resto-Mod 1987 IROC-Z Clone
Engine: Alky fed L92 Vortec Twin-Turbo 6.8L
Transmission: My own built/ design 4L80M
Axle/Gears: Custom 12 bolt (4.10:1)
Re: Weird "clunk" when in gear and off the throttle
...plus even a Tranny Mount in combination.
Thread Starter
Joined: Nov 2012
Posts: 672
Likes: 16
From: Michigan
Car: 1988 IROC-Z/G92
Engine: 5.0
Transmission: T-5
Axle/Gears: BW 3.45 Eaton Truetrac
Re: Weird "clunk" when in gear and off the throttle
Interesting! I imagine I notice it more due to the tunnel mounted torque arm?
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From: Colorado USA
Car: '83 Firebird (T/A Clone)
Engine: 350 with L-69 components
Transmission: 700R-4, 2000 RPM stall converter
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Re: Weird "clunk" when in gear and off the throttle
My guess is tranny mount..
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Thread Starter
Joined: Nov 2012
Posts: 672
Likes: 16
From: Michigan
Car: 1988 IROC-Z/G92
Engine: 5.0
Transmission: T-5
Axle/Gears: BW 3.45 Eaton Truetrac
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