C5 does not slow down
09-01-2018, 07:29 AM
#1
Racer
Thread Starter
C5 does not slow down
when I am on a flat surface and get up to posted speed and take my foot of the gas pedal my
car does not slow down? Why is this. Should the car not slowly come to a stop. Thx
car does not slow down? Why is this. Should the car not slowly come to a stop. Thx
09-01-2018, 08:27 AM
#2
Team Owner
Eventually it will, at least to the point of the engine slowing down to idle speed, and if the car is in gear, a low enough gear, the car will then chug along at whatever car speed equates to a 7-800 RPM engine speed.
09-01-2018, 01:45 PM
#3
Race Director
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2022 C5 of the Year Finalist - Modified
2020 C5 of the Year Finalist - Modified
St. Jude Donor '17-‘18-'19-'20-'21-'22-'23-'24
I had a problem like this recently. I had pulled my ported throttle body off to do a little clean up and put an old throttle body on. Apparently something had "gunked up" around the butterfly keeping it from always closing when my foot came off the gas pedal. I used a little brake fluid as a cleaner and then air to blow everything out. It's worked good since then.
09-01-2018, 08:12 PM
#4
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I don’t like to diagnose based on just symptoms but I would look at the APP & TPS sensors...might be a little wonky...ANY DTC’s set ?????
09-02-2018, 09:20 AM
#5
Racer
Thread Starter
Thanks no codes. This is a automatic drive. We have some flat long stretches of road and when I get yo around 40 mph ant take my foot of the she will just keep going. I will investigate the throttle body butterfly. Sounds like my first stop.
09-02-2018, 10:20 AM
#6
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Just use some good TB cleaner !!
09-03-2018, 11:13 AM
#7
Zen Vet Master Level VII
As about if your TB is sticking, clean it with a cleaner and a good rag. If you car is "coasting too long" I'm not sure you have a problem? Your car sounds balanced, the bearings are lubed, adjusted correctly and leaving your engine in gear will naturally provide forward motion even at low RPMs.
If you feel that the car is not slowing down fast enough, apply your brakes.
Last edited by billschroeder5842; 09-03-2018 at 11:14 AM.
09-05-2018, 03:49 PM
#8
Safety Car
Tbs and or iat. I had that happrn on a 4 door ford. I had to put the car on neutral every time i stopped, of course i had to wait 20 minutes in order to restart tbe car too.
09-06-2018, 01:27 AM
#11
Drifting
09-06-2018, 07:22 AM
#12
Team Owner
09-07-2018, 03:01 PM
#17
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St. Jude Donor '08
Your Throttle Blade cant be stuck because that would set a DTC or put you into reduced engine power due to the difference between what the Accelerator Position sensor and the TPS voltages would be. Its a fail safe circuit and will not allow a mismatch between the two.
I wont say that the Throttle blade wont be dirty but its most likely isn't staying open.
IMHO, If the engine revs when you put it in neutral, you would have a stuck accelerator position sensor. If it doesn't rev, your are just coasting
09-14-2018, 11:39 PM
#18
Racer
Thread Starter
100% on the mark!
Your Throttle Blade cant be stuck because that would set a DTC or put you into reduced engine power due to the difference between what the Accelerator Position sensor and the TPS voltages would be. Its a fail safe circuit and will not allow a mismatch between the two.
I wont say that the Throttle blade wont be dirty but its most likely isn't staying open.
IMHO, If the engine revs when you put it in neutral, you would have a stuck accelerator position sensor. If it doesn't rev, your are just coasting
Your Throttle Blade cant be stuck because that would set a DTC or put you into reduced engine power due to the difference between what the Accelerator Position sensor and the TPS voltages would be. Its a fail safe circuit and will not allow a mismatch between the two.
I wont say that the Throttle blade wont be dirty but its most likely isn't staying open.
IMHO, If the engine revs when you put it in neutral, you would have a stuck accelerator position sensor. If it doesn't rev, your are just coasting
