I have a 2005 Volvo XC 70. For the last six months or so I am experiencing a very intermittent issue. Every once in a while the car starts to idle rough but then it returns to normal, sometimes while driving, even on highway, the car looses power, as if it ran out of gas but than, after a a couple of seconds, things return to normal. Last week, things got worse, as soon as the engine turned on, it ran for about 10 seconds and then it stalled. I ended up having to tow it to my mechanic but by the time the mechanic got to working on it, (it was the weekend so it was about two days later), things somehow miraculously returned to normal.
All diagnostic tests point to fuel related issues (low fuel pressure, etc; can’t really remember them all) but, given the fact that the issue is so intermittent, there is no clear diagnosis so far.
I changed the throttle body, air mass sensor, fuel pressure sensor and fuel filter so far but nothing really helped.
Any ideas would be much appreciated.