my s40 2.0 diesel has rough idle. i tried to clean up throttle body and mas sensor, but still same. i then disconnected each fuel injector seperatly and 3 of them resulted in a further drop in revs, however the 4th when disconnected, did not alter the idle, is this a sign that the 4th injector is needing replaced? forgot to say that when car idling, it wont rev above 1100 revs,( i think car is in "limp home mode") will this correct itself if new injector is fitted? Car is a 2005 volvo s40 2.0d. (Also there is no warning lights / engine diagnostic lights come on on the dash.)
Hello and welcome to our web page here my name isXXXXX a Certified Volvo Car Expert Mechanic.I'm going to try today to answer your question.
yes fuel injector can be bad or clogged up
but you must first read error codes with scanner to make sure there is no electrical sensor going bad
I would not replace injectors now until you test first and hook up scanner you will be going to Volvo garage to run those test
have just noticed couple of air bubbles in fuel line just before fuel filter. could this be cause, and just need fuel system primed to remove bubbles?
can a normal garage do the diagnostic test? want to try avoid main dealer prices. what could have caused air in fuel? had no prob previously.
Ok. cheers XXXXX XXXXX help. thanks again.