Omega Owners Forum - Better when cool

JasonH

Senior Member

Offline

Posts: 953
Bristol
Gender: male

Better when cool
23. Aug 2006 at 20:39

I've noticed that on cooler days my car runs smoother.

When the ambient air temperature is high the car definitely has a lumpier tickover and just doesn't rev as smoothly. It's not to do with engine temperature either because the effect is fairly immediate. Hot day, cold start = lumpy, then stays lumpy.

I'm thinking air intake temperature sensor and/or MAF.

No error codes and car otherwise fine.

Thoughts anyone. What about cleaning the sensors?

Back to top

IP Logged

Tezray Intermediate Member Offline Posts: 264 Bristol Gender: Drives: Omega MV6	Re: Better when cool Reply #1 - 23. Aug 2006 at 20:48 Are you sure it's not just to do with air humidity/density? Because these factors do have a definite impact on performance and unfortunately there's not a lot you can do about it....Is it really very noticeable? I notice it in mine, but i am very picky/sensitive to things like that lol
Back to top	IP Logged

JasonH Senior Member Offline Posts: 953 Bristol Gender:	Re: Better when cool Reply #2 - 23. Aug 2006 at 21:40 I'm really picky too! I suspect someone else wouldn't notice the difference - but I do!
Back to top	IP Logged

tunnie Over Active Poster Offline Posts: 22520 London, W3 Gender: Drives: 2.2 CD (LPG'd) & BMW R1200 GS	Re: Better when cool Reply #3 - 23. Aug 2006 at 22:16 my car runs much better on a cooler day, most cars do.
Back to top	Do you break V6's as often as TheBoy? Then you need tunnie's towing services, recovery costs are just the humiliation of being towed by 2/3's of an engine IP Logged

Markjay Omega Lord Offline Posts: 5452 London Gender:	Re: Better when cool Reply #4 - 23. Aug 2006 at 22:17 ...what grade oil do you use? 10w40?
Back to top	Alas, no more Omegas.... IP Logged

JasonH Senior Member Offline Posts: 953 Bristol Gender:	Re: Better when cool Reply #5 - 24. Aug 2006 at 08:48 Vx 5W30 full synth, long life. Oh no an oil thread....
Back to top	IP Logged

Marks DTM Calib Administrator Offline Ex Member Posts: 25671 Northern Hemisphere Gender: Drives: Astra J, Mum Bus, Dexta Tractor, 108 DMU wip	Re: Better when cool Reply #6 - 24. Aug 2006 at 08:56 Well they are bound to run better on a cold day. Have a read of the MAF sensor FAQ and consider that when its cold, the air mass is higher and hence you can get more air into the engine.
Back to top	IP Logged

mjl1644 Newbie Offline Posts: 9 Northeast Drives: Omega TD auto	Re: Better when cool Reply #7 - 24. Aug 2006 at 13:37 ...perhaps this is why they invented Intercoolers.... mike
Back to top	IP Logged

Markjay

Omega Lord

Offline

Posts: 5452
London
Gender: male

Re: Better when cool
Reply #8 - 24. Aug 2006 at 14:05

I am a bit confused about the fact that the difference is when idling - I think the air volume should have more of an impact at high engine revs.

Going back to the oil issue... (I know, I know Grin

)

The 5W-30 is a new full-synth oil from Vx (replacing the older 5W-40), so I am assuming that you only recently started using it - can you tell if this rough idling on hot days issue was there from the start, or did it appear after you first changed the oil to 5w-30?

Back to top

Alas, no more Omegas....

IP Logged

JasonH Senior Member Offline Posts: 953 Bristol Gender:	Re: Better when cool Reply #9 - 24. Aug 2006 at 14:47 It was there with 5W40 too. TBH it's not that bad, but it's noticeable.
Back to top	IP Logged

zoltron Newbie Offline Posts: 41 Blackheath, Rowley Regis Gender: Drives: Omega Elite 2.5 V6	Re: Better when cool Reply #10 - 24. Aug 2006 at 22:33 I'm a complete fool when it comes to how engines work but as I always understood it the colder the air entering the engine the more it aids combustion, is this the basic principal of performance cars?
Back to top	IP Logged

This is the old site. Please use the new site.

This is the old site. Please use the new site.

www.omegaowners.com/forum/index.php.

This is the old site. Please use the new site.

	Welcome, Guest. Please Login