Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: 2001CatOwner on 13 August 2007, 22:34:30

Title: Scan of Rich mix
Post by: 2001CatOwner on 13 August 2007, 22:34:30
I ran a OBDII scan as my car was hesitating.  It told me my Bank 1 & 2 was too rich.  I was told it was  fuel pressure.  What do you all think.  And i have this ticking sound after i engage the gear out of park, anyway to rid of the ticks
Title: Re: Scan of Rich mix
Post by: TheBoy on 13 August 2007, 22:39:19
I would say more likely the o2 sensors, as fuel pressure could be trimmed back by ecu
Title: Re: Scan of Rich mix
Post by: JasonH on 13 August 2007, 22:43:39
Leaking exhaust manifolds? Air gets in, ECU thinks lean and richens up the mix?
Title: Re: Scan of Rich mix
Post by: Matchless on 13 August 2007, 22:45:19
What trouble codes were stored?
Did someone measure the fuel pressure? If yes then you have either a faulty fuel pressure regulator or the fuel return pipe to the tank is blocked or squashed somewhere. If no then get the pressure measured.

Has any work been done recently around the air intake trunking or around the back of the engine?
Title: Re: Scan of Rich mix
Post by: Matchless on 13 August 2007, 22:47:38
Quote
I would say more likely the o2 sensors, as fuel pressure could be trimmed back by ecu

Fuel pressure is not controlled by ecu. In response to a rich mixture signal from lambda sensors the ecu can only shorten the injector pulse duration (over a limited range)
Title: Re: Scan of Rich mix
Post by: Kevin Wood on 13 August 2007, 22:49:36
I must admit, with both banks complaining, I'd be looking for something common to both, so fuel pressure may be a possibility although fuel pressure regulators are pretty reliable things. Could be that something has taken out both lambda sensors.

Ticks could point to exhaust leaks, however, which ties in with JasonH's idea.

Would be good to get the exact fault codes, though.

Kevin
Title: Re: Scan of Rich mix
Post by: TheBoy on 13 August 2007, 22:49:59
Quote
Quote
I would say more likely the o2 sensors, as fuel pressure could be trimmed back by ecu

Fuel pressure is not controlled by ecu. In response to a rich mixture signal from lambda sensors the ecu can only shorten the injector pulse duration (over a limited range)
Sorry, correct, thats what I meant - ecu would trim down mixture via injector pulse length...

I'm obviously tired, so bedtime for me!
Title: Re: Scan of Rich mix
Post by: cem_devecioglu on 13 August 2007, 22:50:01
Agreed ...lambda sensors or less possibly MAF
Title: Re: Scan of Rich mix
Post by: Matchless on 13 August 2007, 22:53:01
Quote
Leaking exhaust manifolds? Air gets in, ECU thinks lean and richens up the mix?

Its the lambda sensors that are indicating insufficient O2 in the exhaust which is a 'go lean' signal.
Title: Re: Scan of Rich mix
Post by: Matchless on 13 August 2007, 22:58:39
Something common to both banks...

Air mass meter indicating much greater air flow than actually flowing....faulty / wrongly connected?
Coolant temp sensor faulty / not connected.
Title: Re: Scan of Rich mix
Post by: 2001CatOwner on 14 August 2007, 21:53:22
I had installed a cold air in take... if thats the cause what would you all suggest for intakes.
Title: Re: Scan of Rich mix
Post by: Matchless on 14 August 2007, 22:56:47
Quote
I had installed a cold air in take... if thats the cause what would you all suggest for intakes.

Check that you didnt mix up the air temp and multi-ram connectors when playing with the intake.
What air filter are you using....is it one that is oiled? could be that oil has coated the airmass sensor element giving incorrect signals.

The standard intake takes air from infront of the radiator and delivers it to a large panel filter so I wouldnt expect any improvement from intake mods except an increase in noise.