Hi . I own a Volvo S40 2.0 petroleum 2011 year. My problem started few months ago and has been aggravated. First in the morning car doesn't start with the first attempt. The second time it's start and has a rough idle. Recently I have noticed a rise in gas consumption. Some time it has high rpm on idle (1000) and has vibrations, and sometime runs smooth. I have replaced sparks plug checked coils and clean throttle. My mechanic doesn't have a clue, but I doubt in throttle body musfunction. Any idea? Thanks

 

Check error codes , did your mech do a diagnostic ? could be many things fuel regulator, fuel pump , , but sound like fuel problem good luck

 

Should position 1 and 2 of TP have the same value?

 

No that looks normal, when one goes up the other goes down. Just make sure the nominal throttle angle is the same as the current throttle angle. Should be in the same module.

 

Hi my wheel vibrations camed from engine mounts. Replaced and now car it's fine.
What is not solved is the fact that car doesn't start good only in morning ( shut downs in the first attempt and rpm fluctuate from 1200 to 600 for 4-6 seconds) and rpm stays at 945 during day. It should stay 800 rpm I guess!!!
Today I changed the throttle body and problem persist. So I have changed spark plugs, checked coils, and throttle and again the problem of morning start is not solved . I m going to check manifold for cracks and presion tubes. Any other idea??
Thanks guys 😁😁😁😁.

 

Has your PCV system ever been serviced? While the car is idling, take the oil fill cap off and put your hand over it to see if you feel suction or pressure. At idle, suction is good, pressure is not. If you can't tell, look up "PCV glove test" to see examples on how it looks with a latex glove. What does your fuel trim look like? Any whistling coming from the engine at idle?