08-10-2020, 02:46 AM | #1 |
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Engine stutter
F25, issue when towing caravan, engine appears to stutter, miss fire type symptom. Also at slow speeds and when changing up gears without caravan. No errors or engine management lights or indications. BMW diagnostic testing showed no faults indicated.
I have heard this could be tyre wear that is affecting the performance. |
08-10-2020, 07:00 AM | #2 | |
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Engine type? Mileage? Tire type? Vehicle well serviced?
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Mike Thompson0.00 |
08-10-2020, 07:46 AM | #3 | |
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08-10-2020, 12:20 PM | #6 |
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3 litre diesel M Sport
54,000 miles owner from new Full BMW service history Tyres Bridgestone all round Front 6 mm Rear 4 mm It is a stutter, when pulling through the gears. Rev counter shows no sign of dipping etc. |
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08-10-2020, 02:52 PM | #7 |
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ZF8 auto transmission?
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08-11-2020, 09:27 AM | #8 |
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Drives: 2018 X3 M40i, 2012 X3 Xdrive35
Join Date: Aug 2012
Location: Moraga, California
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Any chance you have a bad tank of diesel with water?
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08-13-2020, 02:12 PM | #10 |
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08-13-2020, 04:18 PM | #13 |
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So apparently the front tires had 2mm less tread depth than the rears, right? and when towing, that made the difference? Meaning the X3 was using the fronts (and the rears) to pull with but with the rear load it must be that the front of the cars suspension had dropped enough that the front tires could not get full time traction and what you felt was the slipping of the tires. Correct? So what is the tread depth of those front tires?
If memory serves me well, something like 1.6mm is the minimum legal depth in most states which is around 2/32". |
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08-14-2020, 07:12 AM | #15 |
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I find this very bazaar, not sure what to really make of it. Even 5mm should be ok on the front. 2mm is like 5/64", I can't see how that made any difference. I wonder if there is something else going on that changed when you swapped the tires? Where the front and the rear tires new when you installed them? How many miles are on them now?
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08-14-2020, 01:41 PM | #16 |
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It means the tires aren’t balanced/worn or bent rim. The vibration is probably still present just not as noticeable when in the rear as your not feeling the vibration in steering wheel.
The best and easiest way to check for in proper balance is to find your speed you have a vibration at and accelerate, if the vibration goes away it means something is unbalanced. A worn universal joint can also cause these types of vibrations but usually you will feel in the seat |
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08-14-2020, 01:50 PM | #17 |
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F25 Engine stutter
A Master Technician from BMW first suggested that it was worn tyres and said that he had seen this before. I discussed this with a workshop manager from BMW who also confirmed that this could cause issues as all measurements are gathered from wheel speed sensors, which are then used to compensate any wheel slip or lack of grip using the X Drive train system.
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