hello all. First Id like to start this post by saying I have been with the Volvo family for 7 years now and love the vehicles to death. Secondly Im currently employed by a local dealer.
As for my problem its like this. I first started noticing my car was running rougher a few weeks back. So I checked the ignition components and found most of it to be original. I replaced cap rotor plugs wires fuel air and all fluids with genuine parts. i also have emissions codes for the air pump systems which I know needs serviceing due to the ceased pump an faulty check valve. After chaning all these components the car is running great except for the the original problem. At or around 4500 rpm on a hard take of it stumbles and sometimes puts out a missfire code on cyl #1. Now I cleared the codes again reinstalled new plugs and everyting seemed to be fine. On this past weekend I was checking to see if the problem still exsisted nad sure enough I hammered the gas and this time aorun 5000rpm it partialy stumbled but carried on and no codes. I spoke with both of my master techs and they seem to think that my M.A.F is go to go otherwise I would have fuel trim codes which I dont and my O2s seem to be switching fine. So im kinda at a stand still. Im going to check fuel pressure as soon as my new gauge arrives shop gauge broke last week. I lookin for any suggestions or if anyone has come across this in the past?