My wife's low mileage (27,000) 2001 XC has experienced a very infrequent and very short duration engine hesitation during turns. This has happened only three times (all spaced over the last year) and only lasts a second or so. Two times it was on a right turn and once on a left. On two of the occasions the fuel gauge showed a little less than 1/4 full (we normally keep it fuller) and I'm not sure about the other time. No messages are triggered on the display panel and the check engine light is not on after the event (and I assume doesn't come on during the event but cannot be sure). During the last event my wife did notice the tach needle drop down and then immediately recover. It was still under warranty when it first happened so I took it to the dealer who found nothing (no codes were triggered).
- Has anyone else experienced this symptom ?
- Any thoughts as to a cause ?
- While I suspect it is not the cause, does anyone know if a code would be triggered or the check engine light would come on if the fuel supply were momentarily interrupted (such as by fuel sloshing around during a turn with a somewhat low tank level) ?

Dirt or a broken baffle inside the fuel tank? These problems should become much worse when the fuel runs quite low. Taking a hill might do the same as a turn if the problem is inside the tank.

Unless your car has a defective pickup tube in the tank, I would not point a finger at low fuel levels. My cars are always run until the fuel light comes on before I tank up, and I have never had a cornering problem.
I would think that you would get at least one error code if the fuel pressure dropped to zero, but that the error code would disappear when the pressure came back up. Otherwise the dealers would make a fortune clearing CELs when all of us dummies ran out of gas!
I would check the electrical connections at the AMM and other components that have one end on the engine block and the other on the fenders. Just to elimate any loose plugs.

Klaus
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(V♂LV♂s 1975 164, 1995 854T, 1998 V70R)

KlausC - Thanks for your input. I took your advice and went over the electrical wiring and connections. Found nothing obvious. The wiring also survived my "wiggle test", moving things around with the engine running hoping for the engine to sputter.
Perhaps it is just coincidence, but I now realize that I went almost four years before the first event which occurred about a month after the dealer changed out the electrical cooling fan under a Volvo recall. I'm not sure what had to be taken apart for this replacement but it doesn't appear ignition or fuel electrical connections should have been involved. One thing I did find wrong which was obviously the result of this repair was that the engine fresh air intake tube was loose and totally disconnected from the air filter intake box, which would have allowed hotter than normal engine compartment air to enter. While I can't relate this to my symptoms, I hope that air does not get hot enough to shorten the life of the AMM. ( I know that this can happen with such a poor design as found on my '86 740 turbo where the failure of the air box temperature sensor allows pre-heated air to constantly enter and eventually fry the AMM ) Also, with that tube totally disconnected, the air box was not as secure and "floated" more, allowing the AMM wiring to move a bit more than normal. Still, this is probably just grasping at straws! Time will tell.

LOL Don't you hate it when you bring the car in to a mechanic and then something happens a few days later, totally unrelated?
Good find on the air box, now check the air supply hoses from the box and look for any cracks.
Hopefully all is solved.

Klaus
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(V♂LV♂s 1975 164, 1995 854T, 1998 V70R)