Jerking Motion
tonyjames37
11-23-2009, 08:46 AM
It started yesterday. I started the car and started to drive then all the sudden like jerking motion. I was going about 20-25 mps. Ive noticed when on the highway at higher speeds no jerking. What is wrong? Anyone have an idea?
way2old
11-23-2009, 11:18 AM
When was the last time it was tuned up? Also year of vehicle gives more options to what is wrong
tonyjames37
11-23-2009, 11:47 AM
the yr of the vehicle is 99-2000 and i dont know the last time for a tune up. I got the car from my dad in Sept.
danielsatur
11-23-2009, 12:31 PM
How about some new Plugs, Air filter, MAF sensor, and a throttle body cleaning.
The Silver Goat
11-26-2009, 04:02 PM
What year, how many miles and what's been done to the vehicle as far as maintenance? Could be plugs or a fuel filter...
Blue)(Fusion
11-27-2009, 03:18 PM
Happened to me a few times. Sometimes it would go away after a few seconds to a few minutes. That was caused by the plugs getting fouled with fuel. Once it burned off,all was good.
One time, it continuously jerked due to a bad misfire. It was a failed Coil-On-Plug (COP). Replaced that and at the same time, replaced all the plugs and all was well again.
To test for a bad COP, pull the electrical connector off of the COP one at a time. Each time you will hear the engine change RPM and run more rough. That indicates the COP is working. Plug the connector back in and move onto the next one. When you pull the connector of the bad COP, the engine will not change RPM or toughness. That is the bad COP. Remove it, replace it, and enjoy.
One time, it continuously jerked due to a bad misfire. It was a failed Coil-On-Plug (COP). Replaced that and at the same time, replaced all the plugs and all was well again.
To test for a bad COP, pull the electrical connector off of the COP one at a time. Each time you will hear the engine change RPM and run more rough. That indicates the COP is working. Plug the connector back in and move onto the next one. When you pull the connector of the bad COP, the engine will not change RPM or toughness. That is the bad COP. Remove it, replace it, and enjoy.
The Silver Goat
11-29-2009, 08:06 AM
Happened to me a few times. Sometimes it would go away after a few seconds to a few minutes. That was caused by the plugs getting fouled with fuel. Once it burned off,all was good.
One time, it continuously jerked due to a bad misfire. It was a failed Coil-On-Plug (COP). Replaced that and at the same time, replaced all the plugs and all was well again.
To test for a bad COP, pull the electrical connector off of the COP one at a time. Each time you will hear the engine change RPM and run more rough. That indicates the COP is working. Plug the connector back in and move onto the next one. When you pull the connector of the bad COP, the engine will not change RPM or toughness. That is the bad COP. Remove it, replace it, and enjoy.
Thank for this Blue - I was wondering how to determine which COP had gone bad once it happens. This will work for my 04 GTO as well...
One time, it continuously jerked due to a bad misfire. It was a failed Coil-On-Plug (COP). Replaced that and at the same time, replaced all the plugs and all was well again.
To test for a bad COP, pull the electrical connector off of the COP one at a time. Each time you will hear the engine change RPM and run more rough. That indicates the COP is working. Plug the connector back in and move onto the next one. When you pull the connector of the bad COP, the engine will not change RPM or toughness. That is the bad COP. Remove it, replace it, and enjoy.
Thank for this Blue - I was wondering how to determine which COP had gone bad once it happens. This will work for my 04 GTO as well...
Blue)(Fusion
11-30-2009, 12:27 AM
By the way, if you don't want to dump raw fuel into your cylinders and cats, you can just pull the fuel injector connector instead of the COP connector. Since they're just as accessible on the 4.6L Modulars, I just pull those instead. Not sure what it's like under the hood of the GTOs.
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