Slight vibration felt through gas pedal?
I would tend to agree with you at this point Dr. Bill. Last night I noticed something very interesting. I was driving on a section of road that was going downhill. As such, I was coasting and not giving it any gas. While coasting I felt the vibration still through the steering wheel, but here is what was strange about it. It was pulsing. I would feel the vibration for a second, then the next second nothing. It was as if it was switching on and off.
i too have this vibration but it's not as severe as you guys are experiencing. I can feel it a very low rpms much like how my bike lugs when it's in too high a gear for your rpm range.....
2009 5.7, Crew, 4x4, 3.92, non-adjustable pedals,
build Oct. 08(i think, will check later)
2009 5.7, Crew, 4x4, 3.92, non-adjustable pedals,
build Oct. 08(i think, will check later)
Are you all ready for solution:
here it is believe it or not: check your spark plugs one of them will be dirty with oil or coolant
or at night spray your spark plug wires and ignition coils with water spray to and look for spark arcing while the engine is working to identify bad cable. That massage feeling is not suspension related it is not TB related, not tire problem because you will notice the same thing even when the car is not moving. Start your engine and apply the same amount of pressure on the gas pedal while you are in park and tune to the exact rpm level and keep it there you will constantly feel the same vibration and your engine at that point will sound like purring cat. That is ignition related problem. Check all spark plugs and re gap all the plugs to specs. good luck. Had this same exact problem on my 3100 gm engine, and came here registered just to tell you people what the solution is...... how nice
here it is believe it or not: check your spark plugs one of them will be dirty with oil or coolant
or at night spray your spark plug wires and ignition coils with water spray to and look for spark arcing while the engine is working to identify bad cable. That massage feeling is not suspension related it is not TB related, not tire problem because you will notice the same thing even when the car is not moving. Start your engine and apply the same amount of pressure on the gas pedal while you are in park and tune to the exact rpm level and keep it there you will constantly feel the same vibration and your engine at that point will sound like purring cat. That is ignition related problem. Check all spark plugs and re gap all the plugs to specs. good luck. Had this same exact problem on my 3100 gm engine, and came here registered just to tell you people what the solution is...... how nice
3100,
Thanks for the info, but I don't think that is the problem that I am experiencing. Too many new trucks, too few miles to be plugs unless the plugs or wires are bad. It is possible, but not likely. I did put your explaination to test and my truck does not make any vibration at any RPM other than idle while on the driveway. It seems to need some type of loading on the engine. I really think this is a harmonic problem, not ignition and not MDS. If someone can reproduce or shed light on this issue, please let us know.
Thanks for the info, but I don't think that is the problem that I am experiencing. Too many new trucks, too few miles to be plugs unless the plugs or wires are bad. It is possible, but not likely. I did put your explaination to test and my truck does not make any vibration at any RPM other than idle while on the driveway. It seems to need some type of loading on the engine. I really think this is a harmonic problem, not ignition and not MDS. If someone can reproduce or shed light on this issue, please let us know.
WVU pm'd me about this. i figured id reply here so everyone else can know also.
TSB only applies to vehicles built BEFORE 10-3-08.
· Spark Knock between 1800 to 2500 RPM.
repair is to flash PCM w/ updated software.
second TSB for slightly rough idle, applies to vehicles built BEFORE 10-3-08:
TSB only applies to vehicles built BEFORE 10-3-08.
Some customers may experience:
·
NVH issues while the vehicle is operating in the MDS mode.
· Spark Knock between 1800 to 2500 RPM.
repair is to flash PCM w/ updated software.
second TSB for slightly rough idle, applies to vehicles built BEFORE 10-3-08:
Some customers may complain of the idle quaility after the vehicle is warmed up. This
condition can happen while the vehicle is in park, neutral, drive or reverse with no
additional throttle tip in. A software change has been made to the increase the warm
nominal idle speed from 584 rpm to 648 rpm, which corrects the condition.
If the vehicle owner complains of this issue reprogram the PCM with the new software.condition can happen while the vehicle is in park, neutral, drive or reverse with no
additional throttle tip in. A software change has been made to the increase the warm
nominal idle speed from 584 rpm to 648 rpm, which corrects the condition.
Great news Savage. Mine was built in 8-09 and shows both of these problems. Mine has always had too rough of an idle at of course idle. I have received the notice for the update, but was waiting for the OAT fix to get them done at the same time. Thanks for the news.
Yes, thanks for the information, Savage. How would I know if mine was built before 10-3-08? I see the manufacturing date of 10-08 on the sticker inside the driver's door. Is there somewhere that lists the specific day?
At some point I need to take it back to the dealership for a couple other things anyway. At that time I'll just tell them to hook it up to the Starscan and check it for any available updates.



