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Occasionally when accelerating, my car will kind of 'stall-out', almost like it's choking. I'll hit the gas but the car won't really get up to speed unless I floor it and it kicks up and gets itself together. Also, almost always when this happens it's accompanied by the check engine light coming on briefly. I've also noticed it has happened while driving straight up to speed on the highway it seems to do the choke out thing. It's kind of scary, not sure what it is. I would deeply appreciate anyones suggestions from those who have an understanding of what this could be. Most of the time however, the car will rip right out of dead stop fine and it's fantastic but when this happens it's definitely disconcerting and unsafe. Could it possibly be transmission related? That's the only thing I can think of but the transmission seems to shift fine. help!! lol.
 

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Humble E34 lover
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Have the codes pulled to find out what caused the CEL. Given the descirption you give, it could be your MAF, but you won't know until you have the codes pulled. Doing anything without knowing the fault code is like shooting target practice in the dark.
 

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Humble E34 lover
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Humble E34 lover
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I would think that if he replaced the coils (6 individual coils, not a coil pack) and the plugs with new ones, then that would eliminate those items as the cause of your misfire. I suppose it is possible that your crank position sensor or camshaft position sensor may be giving up the ghost, but again, without a definitive diagnosis, you will be throwing darts at a target 50 yards away in the dark.

Maybe someone else on this forum that lives in your area can recommend a reputable independent mechanic to diagnose your problem for a definitive fix. I wish I could help more.

Steve
 

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Russell
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interesting, I have something similar. The engine seems to stumble or seem to miss when running under about 2500 rpm and I slightly increase throttle. Seems to have gotten worse in the past month or so. Higher speeds seems to run fine. I was considering coils as well. Mine are original with coil to plug connectors installed within the last two years. I have also considered the vanos unit not reacting properly. Could also be the injectors as they are original and never been removed and cleaned/calibrated.

In my case, I do run Technon Fuel injector cleaner or similar several times a year. My fuel is mostly Shell 93 or chevron 93 (until they moved out of KY) Fuel filter is 19,000 miles old. Another thought is the lousy E10 gasoline we get here in KY. No E0/pure gas anywhere except at a few marinas.
 

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Manualaholic
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I had an issue very similar to yours that triggered the check engine light. It turns out if was a dying fuel injector.
I would toss a bottle of injector cleaner into the tank before your next fill up and see if that helps it any.
How old is your fuel filter as well?
 

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Humble E34 lover
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Good call goosefoot. I keep forgetting that the injectors are electronic and not mechanical.

OP, go have the fuel injectors checked out. You may just have one going bad.
 

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I have a similar problem, and I've replaced my fuel filter and the MAF. I had it in to a mechanic and he said I needed to replace the throttle actuator, which was about $1400. Problem is, when I look on line or go to an auto parts store, I can't find a throttle actuator! Maybe the throttle switch?
 

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The Biggest P0st Whore!!
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I've had the under 2500 rpm hesitation crop up a few times. Mine cleared up after 3 or 3.5k.

Fixed it twice with a new coil. When it came up again I just replaced all of them. No problems since.

You believe he switched them? How much do you trust him. If he did replace them the bill should be a clear indicator (over $300 in coils). Did he replace the connectors too?
 

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I would see if you could find a coil in a junkyard and injectors. Do the testing yourself and save a bunch of money. If you can do it. I have the same problem currently and its leaning heavily on the fuel injectors. Only problem have with mine though is that it runs very rich, so its possibly an O2 sensor sending the wrong messages to your ECU which would absolutely make your car run like hell.

(Similar O2 issue in my 03 IS300, pos it was)
 

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i know the thread is pretty old.

so did the coils make the difference. i have a 525i i have the same problem, i have a hesitation to get it to move, but afterwards its pretty good.

i was told the car model itself was slow of the line. I have no check engine light or anything.

what do u guys think
thanks
 

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1. Clogged fuel filter. Remove, rinse out 5 times from both ends with plain water, stop when clear water alone runs out from both ends, shake dry and reinstall. Or use a new filter.
2. Dirty fuel system. Perform the diesel fuel injector cleaning for 3 successive fillups, and then once every 3 months for as long as you own the car.
3. Unless this has been done recently, do both 1 and 2 together.
4. Vacuum leak. Probably a cracked boot. This can cause acceleration hesitation issues and even misfires.
 
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