SOLD - 2001 Volvo S80 T6: Mobil 1 Oil & Synthetic ATF, Brake Performance drilled and slotted front rotors, Akebono Euro Ceramic pads and Yokohama Avid V4S tires, 91K miles.
I'd take out the plugs and clean or replace them to start. Clean the coil connections with CRC QD electrical contact cleaner. Clean the MAF with CRC MAF cleaner. Clean at least half of the throttle body with CRC throttle and intake cleaner/lubricant -- there's no cable to make butterfly valve open so you have to unbolt ETM from intake manifold to clean other side. And if all else fails take it to a dealer to have things randomly replaced (at your expense) until the problem goes away.
The spark plugs and ignition coils are ok.
About the ETM i dont clean, but i gonna make wen a have courage for this...hehe...
The MAF i change 1 year a go.
A ETM in Brazil dont have waranty, and for replace the cost is about U$ 4.000,00 on dealer.
So i will try repair the car myself.
Thanks for help.
I don't think cleaning the ETM will fix a "faulty signal", but good luck with that anyways. If you need to look-up Volvo ECM codes in the future just go here: http://www.ppc-diagnostic.com/codes/eECM/