2004 Volvo S80 T6 Just replaced all six spark plugs and #6 ign coil that had failed. Also replaced air filter and cleaned MAS with electonic spray.
This work was undertaken due to 12 miles into first ride after Sandy(NJ), the CEL came on and when stopped at destination (2 more miles), the idle was extremely rough and CEL started flashing. When restarted, still rough idle, but a steady CEL. Neutral was not as rough as drive. After starting to drive, acceleration was a problem, but would cruise steady at 35, 40 MPH. CEL would flash for way less than a min( 5-10 sec) when first accelerating then go steady.
So... starting car after replacing noted parts, it idled smooth and seemed fine. I let it idle for about 5 mins while i got ready to test drive. First press of gas pedal (in nuetral)resulted in minimal RPM rise. When put in drive, smooth engine but sluggish on power. Then in text window came "engine performance low" . Stopped and restarted and then message said "engine system service urgent". Any comments on what changing the noted parts would contribute to message received. Does car have to be "reprogrammed", for lack of a better word. Have I created problem requiring Dealer to "reset" anything? Any comments or advice would be greatly appreciated. First time on Volvo. Lots of older VW Passat, Jetta and US car work done over the years. I've been a shade tree mech for all my cars over the last 40 years, just never on Volvo. Especially 2004! (New to me) Thanks again in advance for any comments.

 

I would first check for any loosen coil plugs, but looks like another coil went out.

 

Thanks for reply.

 

Disconnected battery over night. Did remote locks , etc., prior to starting. Started car and it idled fine. CEL was off and the only message said time for regular service. Drove the car gently for 3-4 miles and then I tried a hard acceleration and the car did not respond although the tach rose above 2000. Let off gas and reduced engine performance message came on. Limped back home and at idle was still smooth. After restarting car, messages were clear and no CEL! Took off on another test drive and went fine for 3-4 miles and reduced eng perf returned when gas was pressed for accelerating from 35MPH. It appears plugs, coils, and air filter are not the problem. ???

 

Drove car 12 miles to dealer. 1/4 mile from house reduced performance message came on. Pulled over and turned off for couple minutes. Restarted and car ran all the way to dealer although this was a cruise at 30-40 MPH. No power when pushing gas pedal with engine above 2000RPM. Good idle at stops but take off was just plain lack of power. Never got any other messages. Dealer diagnosed and found three codes. Turbo, Thermostat!,and engine sys. No #codes provided yet. Wants $177 just to take off pipes and plastic covers to investigate further. I'm getting twitches in lower region as dealer grip seems to increase. I said go for it.

 

vida connect... codes ECM-201A Thermostat, ECM-6814 Turbo, ECM-982A Engine control.
Tech removed obstruction in intercooler, software update.
Codes cleared and s80 t6 runs like normal.