Truck jumps
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Truck jumps
Ok i can start driving and the truck takes off fine it does not have a problem when taking off... But when you take you foot out of the gas it start to have hesitation it shakes and jumps... I was told that it was the spark plugs and that i should change them so I did.... Then I was told that it was the wires and changed them too... SO now I am on the TPS and not sure if it is that or if it is something else....I know i need need shocks and shyt... But i don't think that is the problem....i just don't want to throw money at the truck and that not be the problem... SO if you have had this problem... PLEASE tell me what it is that you did... Or what it is that I can do to get the problem takin care of.... Thanks I need really need the help.....
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Is there some way that the spark plug wires should sit too.... It looks like they all should sit the same way... Like the end of the wire should sit facing away from the hole.... I know the plug sit in the head a little sideways... Not up and down.... I have always had four bangers.. ANd then just drop right in... But this truck has me stumped... I can get it to not jump.... Take off no problem but when you try to keep the same RPM speed.. Keeping it at 45 lets say... Getting there is no problem.. But trying to stay at 45 is when it jumps... It's all or nothing with this truck... But sometimes you can feel the the gas petal trying to push back or not wanting to go down... I have checked out the other fourms about this... But just not sure what to do....
Lead Driver
Joined: Sep 2006
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Assuming you have a coil over plug motor, the problem is a coil with shorted turns.
Which one is the problem because it will not set a code as it is not a "hard" fault.
There is a reason it acts the way it does; has to do with fuel and ignition timing changes that take place at low loads and speeds between 45 and 55 mph, that normaly takes place. If a coil is not up to spec a missfire occurrs as a jerking feel.
Good luck.
Which one is the problem because it will not set a code as it is not a "hard" fault.
There is a reason it acts the way it does; has to do with fuel and ignition timing changes that take place at low loads and speeds between 45 and 55 mph, that normaly takes place. If a coil is not up to spec a missfire occurrs as a jerking feel.
Good luck.
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It's a 97 4.6L 4x4... It has the blaster packs... I know that is not the name for them but it does not have a coil... It's the one with the four on one side and four on the other... Today it didn't want to start untill I put the gas petal to the floor board... I am starting to wonder if it has a gas problem... Not getting enuff.. or what ever... Should I go ahead and get new blaster packs.. MSD makes them for my truck and its not much more then the stock ones.. i think 20 bucks more....
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Joined: Sep 2006
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You brought up a new symptom.
Having to put the throttle fully open to start is the way you try to atart a flooded motor.
It stops fuel injection because the PCM detects the TPS as fully open, this clears the gas with only air passing through the cylinders during cranking.
Sounds like weak ignition not firing and causing the cylinders to load up with fuel.
Good luck.
Having to put the throttle fully open to start is the way you try to atart a flooded motor.
It stops fuel injection because the PCM detects the TPS as fully open, this clears the gas with only air passing through the cylinders during cranking.
Sounds like weak ignition not firing and causing the cylinders to load up with fuel.
Good luck.
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Joined: Jan 2008
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I don't think your are describing your problem in an understandable way. First you say the truck "jumps", but then you really confuse things by saying "sometimes you can feel the the gas petal trying to push back or not wanting to go down". This truck does not have drive by wire and I don't believe it's haunted, but by the way you describe it you make one wonder. Have you checked your fuel pressure? There is a schrader valve on the fuel rail. The faster you try to go the more fuel is being asked for from the pump. Have you changed your fuel filter recently? Maybe you have a mechanical bind in the cable going to the throttlebody. Is your floormat wedged under the accelerator pedal? Is the cable binding? Is the throttle blade moving smoothly throughout its' travel?
