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Has anyone noticed this? I seem to be getting a low rpm stumble immediately after pulling away from the service station. It seems to last for the first 50 miles or so. At first I thought it was a bad tank of gas but over the last few months it doesn't matter what brand of gas I use (I always put in 93 octane on the east coast here). It is almost as if I am getting a fuel cut off or hesitation upon load but at rpms <1800. It has a frequency of 1/4 second. It isn't nearly as bad as the jerking from the US software that people notice on acceleration. This is noticed by me on cruising say 40mph but then applying load as if going up a hill. It is concerning enough that I am urged to downshift when normally the torque we're all used to would not give us a second thought. Is this a delayed software adaptation thing? Poor fuel pump pressure? Need for repeat fuel filter (did that 80K miles ago)? Thanks, Dan.
 

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Has anyone noticed this? I seem to be getting a low rpm stumble immediately after pulling away from the service station. It seems to last for the first 50 miles or so. At first I thought it was a bad tank of gas but over the last few months it doesn't matter what brand of gas I use (I always put in 93 octane on the east coast here). It is almost as if I am getting a fuel cut off or hesitation upon load but at rpms <1800. It has a frequency of 1/4 second. It isn't nearly as bad as the jerking from the US software that people notice on acceleration. This is noticed by me on cruising say 40mph but then applying load as if going up a hill. It is concerning enough that I am urged to downshift when normally the torque we're all used to would not give us a second thought. Is this a delayed software adaptation thing? Poor fuel pump pressure? Need for repeat fuel filter (did that 80K miles ago)? Thanks, Dan.
If your fuel filter is 80k miles old I would replace it now whether you had any symptoms or not. For the other issue, I have noticed right after I fill up when I'm stopped at a light that the car shakes more than normal at idle. I don't think I've ever noticed a hesitation while driving. The idle rumble usually only lasts for the first time running the car after fill up. The next day it's back to normal. Can't explain it!
 

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It may not be the adding of gas but rather just the opening of the tank. When you are low on fuel but without adding gas just open the gas cap and listen very close for any sound of air leaving or entering. Then drive and see if it occurs. There are two issues here and you need to rule out one for ease of diagnosis.

I suspect what is happening is when you fill up you are churning up crud on the bottom of the cup that holds the fuel pump and then when you restart that all gets sucked to the screen on the bottom of the pump restricting fuel flow. There are tank vent issues that could cause the same thing ergo the first test.
 

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I have an extra fuel filter that is still good if you like to try this way first. Will be sending you a PM.

I can offer my INPA to see whats going on as long as there is a power connection for my laptop (battery discharged quickly).
 

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Was the handle on the gas pump green? :hihihi: jk, I know were all better than that.

I would suspect the fuel filter as well as it is the first component in line when fuel leaves the tank. Its a cheap and easy fix, and will tell you right away if it is the root cause of your problem, or if you need to look into injectors.
 

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Run a full bottle of Techron to see if it helps clear up the hesitation.
 

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I had the same symptoms as you after every fill up and then fuel pump failed after few months. Change the filter first.
 

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Discussion Starter #8
Thanks, many good ideas here. No I didn't inject diesel or kerosene.;) I'll try to pop the gas cap as suggested when I'm down on fuel and report back. My commute is short presently so I may need to rig up a Ferris Bueller situation.... I could replace the filter but not the most enjoyable of things to do.
 
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