Your car has a hot film MAF snesor that is known to cause running problems and require replacement on a lot of M104 engines. It's hard to say for sure over the internet that it needs replacement without seeing any data or possible stored codes. However, it is a possible culprit, it does take 5 minutes to replace, and the part costs more than $90.

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Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record