I have owned the car for about 1 1/2 yrs. and have been really pleased with its performance. The acceleration, steering response in traffic, stopping and quick starts and dependability has made it a fun car to drive. As time passed, I noticed a low pitched "grumble" on start up but it seemed insignificant. After the car warmed up there was no unusual sound and the SAAB performed very good for having 124,000+ miles. As 2015 December weather turned colder (low 40s, upper 30s), cold start up caused a harsh shaking & the engine struggled to remain running. This persisted until the engine warmed up. After warm up, it ran fine (22 mpg in town: 28 mpg on long trips). I was concerned and had it checked out. A mechanic who is familiar with European cars, found low pressure in cylinders 2 (75 psis) & 3 (100 psis). He said normal was 175 psis as in cylinders 1 & 2. The mechanic suggested this problem could possibly be caused by carbon build up on the valves or piston ring malfunction. But the plugs were not fowled and it was not burning oil. He suggested a repair would cost hundreds even thousands. A second opinion yielded similar results. This mechanic suggested (guessing) using standard rather than premium gas &/or using non synthetic oil could cause this problem. The owner's manual suggests using premium & that is all I used. My thoughts are, the previous owner may have used only 87 octane. Cost to overhaul = approx. $4000. I told him the SAAB with a good engine was worth about $5500 and probably worthless as a trade in as is. He agreed. As one who takes very good care of my cars, I have developed a totally different opinion of the Swedish "Aviation" engineers that designed the SAAB. Although, I have found BMWs and Mercedes have similar problems (my anger extends to the Germans too). My mechanic, after researching online, found this is an unusual problem for which SAAB (now bankrupt) nor GM (which bought SAAB) would help shoulder the financial burden. I'll probably pay the $4000 since buying a newer car is unaffordable at this time. Chagrinned!