Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: apcollis on 07 July 2012, 21:49:49

Title: Poor MPG
Post by: apcollis on 07 July 2012, 21:49:49
Hi Everyone
I have just bought my third Omega but this is the first 2.2 petrol.
I am currently getting 14.6 mpg which seems a bit harsh, the car also has a misfire on first start up if I dont just drive away, if I drive away it doesnt misfire. Can anyone offer any advice?
All the best
Andrew
Title: Re: Poor MPG
Post by: SIR Philbutt on 07 July 2012, 22:50:20
Obvious one is to check plug wells for oil or water. leaky cam cover gasket or widscreen scuttle

Check coil pack while you at it for arcing etc while your at it.

Next thing is breather pipes and ICV (idle control valve) and then maybe throttle body

look in maintenance guides for instructions

MPG can seem bad if you have just reset it and not had a run but some of the above will help with MPG. The 6 pot owners on here will tell you you have 2 less than required  ::)

HTH Phil

By the way put the info of your car in your profile (see mine <---)  so people know what they are talking about
Title: Re: Poor MPG
Post by: Victor Meldrew on 07 July 2012, 22:55:53
Hi apcollis,

My 2.2 petrol can show 18 MPG on a short stop/start jaunt  :'( but give over 40 MPG on a long motorway journey.  :y Average over a tankful is 30 MPG. So with 14.6 MPG I think something is amiss.  Misfire might suggest oil in spark plugs, is the cam cover gasket leaking? Common problem, I'm about to change mine as it's leaking at the back after only 4 months.  A pattern gasket was fitted by a local garage in March. I'm fitting a genuine GM gasket and would suggest you do the same if you find this is the cause of your misfire.

HTH
Title: Re: Poor MPG
Post by: RobG on 07 July 2012, 23:01:42
Obvious one is to check plug wells for oil or water. leaky cam cover gasket or widscreen scuttle

Check coil pack while you at it for arcing etc while your at it.

Next thing is breather pipes and ICV (idle control valve) and then maybe throttle body

look in maintenance guides for instructions

MPG can seem bad if you have just reset it and not had a run but some of the above will help with MPG. The 6 pot owners on here will tell you you have 2 less than required  ::)

HTH Phil

By the way put the info of your car in your profile (see mine <---)  so people know what they are talking about
Not on a DBW Phil ;)
Title: Re: Poor MPG
Post by: SIR Philbutt on 07 July 2012, 23:31:01
Obvious one is to check plug wells for oil or water. leaky cam cover gasket or widscreen scuttle

Check coil pack while you at it for arcing etc while your at it.

Next thing is breather pipes and ICV (idle control valve) and then maybe throttle body

look in maintenance guides for instructions

MPG can seem bad if you have just reset it and not had a run but some of the above will help with MPG. The 6 pot owners on here will tell you you have 2 less than required  ::)

HTH Phil

By the way put the info of your car in your profile (see mine <---)  so people know what they are talking about
Not on a DBW Phil ;)

Thanks for that Rob wont make that mistake again  :-[ . Not an expert just trying to help, he would have found out anyway  ::)

What does DBW stand for  ???
Title: Re: Poor MPG
Post by: noel on 08 July 2012, 08:12:37
Obvious one is to check plug wells for oil or water. leaky cam cover gasket or widscreen scuttle

Check coil pack while you at it for arcing etc while your at it.

Next thing is breather pipes and ICV (idle control valve) and then maybe throttle body

look in maintenance guides for instructions

MPG can seem bad if you have just reset it and not had a run but some of the above will help with MPG. The 6 pot owners on here will tell you you have 2 less than required  ::)

HTH Phil

By the way put the info of your car in your profile (see mine <---)  so people know what they are talking about
Not on a DBW Phil ;)

Thanks for that Rob wont make that mistake again  :-[ . Not an expert just trying to help, he would have found out anyway  ::)

What does DBW stand for  ???
drive by wire  (non cabled accelerator) :y
Title: Re: Poor MPG
Post by: apcollis on 09 July 2012, 02:03:05
Hi everyone, thanks for your replies, its very much appreciated. So far I disconnected the maf sensor and started it which made the misfire better, not sure if I'm going in the right direction or coincidence, I will look at all your ideas tomorrow. Serious bout of man flu has kept me away from the car for the weekend but have to grow up to go to work tomorrow so will check at lunch time. The car is a 2002 2.2 petrol but I will update my profile in a sec. Thanks again everyone so far.