99 S80 surge

Mr Craig · Post by **Mr Craig** » 23 Mar 2011, 08:42

My 99 S80 2.9 surges upon acceleration and also at speed. An auto parts store code reader read that "bank one system to lean" and "bank two system to lean". I cleaned the ETM a while back so I don't think that’s the problem, but what’s the deal with bank one and two on an inline 6?

Post by **jimmy57** » 23 Mar 2011, 11:21

bank one is cylinders 1-2-3 and bank two is cylinders 4-5-6.
There are two front O2 sensors and the fuel mixture (fuel trim) is split.
99 S80 2.9 is somewhat prone to MAF sensor failure and until it gets way out of range there will not be a MAF code but it can run lean. Fuel pressure is also a concern for those codes when set on both banks.
Someone with experience and VIDA or some scan tool capable of full fuel system readout can figure it out. MAF correction factor is usually off too far on bad MAF cars.