Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: mustangboy on 02 November 2009, 22:48:17

Title: Omega auto box. Modulator or No ???
Post by: mustangboy on 02 November 2009, 22:48:17
Hi all.
has my 1998 omega 2 litre automatic  got a vacume modulator on the automatic gear box?.  reason for asking is that when car is cold the engine revs to almost 3500 RPM before it changes from 1st to 2nd gear. once slightly warm it then changes normally.
any ideas  ??
Title: Re: Omega auto box. Modulator or No ???
Post by: rustym95 on 02 November 2009, 22:51:45
have you checked the oil level in auto box,?
Title: Re: Omega auto box. Modulator or No ???
Post by: mustangboy on 02 November 2009, 22:57:14
yes checked the oil level and its fine
Title: Re: Omega auto box. Modulator or No ???
Post by: alank46 on 02 November 2009, 22:59:40
Hi
Its designed to do that to warm up the cat quickly, although 3500 rpm does sound a little bit high.  My 3L revs to about 3000 rpm.
Alan

Quote
Hi all.
has my 1998 omega 2 litre automatic  got a vacume modulator on the automatic gear box?.  reason for asking is that when car is cold the engine revs to almost 3500 RPM before it changes from 1st to 2nd gear. once slightly warm it then changes normally.
any ideas  ??
Title: Re: Omega auto box. Modulator or No ???
Post by: rustym95 on 02 November 2009, 23:13:19
ive seen some were that there is a rev counter for the auto box or somthing like that will change gear when rev's hit a certen speed have you had a look at that, it neds to be right so the gear will change, think some one said he had to leave the engine running for 5 min before he could drive it as would not do anthing until then, he changed the sencor and works fine again.
Title: Re: Omega auto box. Modulator or No ???
Post by: dbug on 02 November 2009, 23:41:36
Quote
Hi all.
has my 1998 omega 2 litre automatic  got a vacume modulator on the automatic gear box?.  reason for asking is that when car is cold the engine revs to almost 3500 RPM before it changes from 1st to 2nd gear. once slightly warm it then changes normally.
any ideas  ??

Its perfectly normal when cold - and by design.
Title: Re: Omega auto box. Modulator or No ???
Post by: davethediver on 03 November 2009, 00:46:15
SOunds fine to me, mine does the same and ATF level is fine in mine.
Title: Re: Omega auto box. Modulator or No ???
Post by: Elite Pete on 03 November 2009, 09:34:16
Quote
ive seen some were that there is a rev counter for the auto box or somthing like that will change gear when rev's hit a certen speed have you had a look at that, it neds to be right so the gear will change, think some one said he had to leave the engine running for 5 min before he could drive it as would not do anthing until then, he changed the sencor and works fine again.
What :-?

As said earlier, its normal but a pain, I used to leave the car idle for a while before setting off ;)
Title: Re: Omega auto box. Modulator or No ???
Post by: Andy H on 03 November 2009, 10:32:30
Quote
Quote
ive seen some were that there is a rev counter for the auto box or somthing like that will change gear when rev's hit a certen speed have you had a look at that, it neds to be right so the gear will change, think some one said he had to leave the engine running for 5 min before he could drive it as would not do anthing until then, he changed the sencor and works fine again.
What :-?

As said earlier, its normal but a pain, I used to leave the car idle for a while before setting off ;)
So the handbook says that the engine is allowed to rev higher before gear changing to aid warm up. Somebody else has said that they changed a sensor to fix a problem.

Logically that would have to be a temperature sensor. If still working but giving an incorrect reading it might not flag up an error code so you would need access to tech2 or "My Naff Code Reader" to see what sensor was giving a garbage reading.

My 2.6 auto revs to about 2000rpm when I first pull away but seems to be almost normal after about 100 yards. It might behave differently when winter sets in  ;)
Title: Re: Omega auto box. Modulator or No ???
Post by: mustangboy on 03 November 2009, 23:20:13
thanks all.  i think i can live with it  :)
Title: Re: Omega auto box. Modulator or No ???
Post by: Grrrrrr on 04 November 2009, 22:29:21
It revs that high even when standing still idling? I'd check that sensor. Mine certainly doesn't rev that high when idling. Can rev a bit high before changing gear when cold though.