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Lou P. master tech
Lou P. master tech, Mercedes Technician
Category: Mercedes
Satisfied Customers: 4966
Experience:  15 years master certified 100% fix rate and have access to factory radio codes, wiring, and instructions.
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When driving on the highway at 75mph my 2007 GL450 started

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When driving on the highway at 75mph my 2007 GL450 started shaking abruptly and the check engine light came on. When I got off at the exit the car was shaking and felt like it would stall. What is wrong?

Hello, my name is***** and i will do my best to assist you.I am going over your story now and will reply back soon with some info,thanks!

Rachel i know you said the check engine light came on but was it flashing at you ?

Customer: replied 1 month ago.
I don't know but from when I got off the highway to parking it was solid
Customer: replied 1 month ago.
I don't think it was

ok, have you started the GL since?

it sounds to me like the engine was misfiring, have you filled gas before this happened?

and by shaking do you mean the engine felt like it was shaking or the car itself? like steering wheel and brake pedal? I am assuming at this point the issue is with the engine.

Customer: replied 1 month ago.
it seems fine when I restarted

ok, so the issue is most likely not a major failure or it would still shake.

what happens is if a cylinder is misfiring the engine module will shut off that cylinder for emissions purposes and to save more parts from failure so the engine will shake and not have as much power.

things that can cause this are

  1. failing spark plugs
  2. failing ignition coil
  3. poor fuel quality due to no fault of your own

how many miles are on your GL?

since the check engine light is on you can drive by a autozone or another parts store and they can read the codes and give you a printout to what the code is, then you can let me know and I can give you some a better idea of what is going on and if it may happen again which is likely.

Let me know what you want to do and i will help you for sure,

Please take a second and click the stars at the top of the screen to rate my service so i may receive my credit , 5 stars is ideal , please request me in the future.Keep in mind that when you rate it does not end our conversation, you can still return here to me for follow up information if needed just simply reply back, thanks!
Lou P.
Master Mercedes-Benz Technician
Master ASE Certified

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