Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: amba on 07 May 2007, 18:53:30

Title: How does it work ?
Post by: amba on 07 May 2007, 18:53:30
Just removed the throttle control sensor in readiness to replace in morning( post office permitting) and was wondering how it worked as it looks no more than a small black case with 3 pins and and plastice rotating cam inside...how do Vauxhall justify charging in excess of £70=00 for it ???
Title: Re: How does it work ?
Post by: Marks DTM Calib on 07 May 2007, 19:00:32
It is nothing more than a volume control......
Title: Re: How does it work ?
Post by: amba on 07 May 2007, 19:23:42
So does it operate by the trottle and then supplies an electrical pulse to the fueling?
Title: Re: How does it work ?
Post by: Matchless on 07 May 2007, 20:00:37
Its a variable resistance ( two actually), a reference voltage is applied between the 'ends' so the wiper connection has a variable voltage in proportion to the throttle opening.
The ECU can also look at the rate of change of this voltage so knows when you snap the throttle open quickly and can richen the mixture to improve drivability and throttle response.
Title: Re: How does it work ?
Post by: Markjay on 07 May 2007, 20:06:31
Quote
Its a variable resistance ( two actually), a reference voltage is applied between the 'ends' so the wiper connection has a variable voltage in proportion to the throttle opening.
The ECU can also look at the rate of change of this voltage so knows when you snap the throttle open quickly and can richen the mixture to improve drivability and throttle response.


Matchless, I have been following your post recently and just wanted to ask: how do you know all these things???  :o

 ;D
Title: Re: How does it work ?
Post by: amba on 07 May 2007, 20:32:37
Sounds quite complicated...so expect that is why it is pricey??lets hope it works
Title: Re: How does it work ?
Post by: Matchless on 07 May 2007, 22:42:55
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Matchless, I have been following your post recently and just wanted to ask: how do you know all these things???  :o

 ;D[/quote]

Wahay!! Ive got my very own stalker!! ;D

I'm an Engineer ( a real one, not a washing machine mechanic pretending to be one) I was trained to take things apart to find out why they havn't broken yet.

(Note, the Engineer's training also contains a compulsory module on cynicism (if it aint broke, it soon will be))
Title: Re: How does it work ?
Post by: Andy B on 08 May 2007, 00:45:29
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...... (if it aint broke, it soon will be))

Or ..... put another way ..... 'fixed beyond repair!!'  ;D
Title: Re: How does it work ?
Post by: Kevin Wood on 08 May 2007, 10:39:17
Quote
I was trained to take things apart to find out why they havn't broken yet.

Ahh, me too! Used to drive my parents mad when I was a lad. I wasn't as good at putting them back together again back then!

I can't accept anything unless I've dissected it and found out how it works...

Kevin
Title: Re: How does it work ?
Post by: ians on 08 May 2007, 10:46:10
Quote
Quote
I was trained to take things apart to find out why they havn't broken yet.

Ahh, me too! Used to drive my parents mad when I was a lad. I wasn't as good at putting them back together again back then!

I can't accept anything unless I've dissected it and found out how it works...

Kevin

Oh no. Me too.

Actually its the putting back together, in the same order, without a few bits left over that I find the challenge..
Title: Re: How does it work ?
Post by: amba on 08 May 2007, 10:52:48
Well I dont know how it works ,but with a different one ,it does ??replacement TPS fitted this morning..very easy...and so far all seems well..nice steady tick over and appears to run smoother so will take it for the usual 100 mile trip to work and back today and see how it goes....think I will clear all fault codes with the 25/30 ignition on/off trick and keep fingers crossed none re-appear again today.
Title: Re: How does it work ?
Post by: Marks DTM Calib on 08 May 2007, 11:04:29
Thats good news.

And yes, they are pretty simple things.....little more than a pair of carbon tracks and some wipers.

The ECU monitors it for two reasons......

1) To determine throttle position (obviously!), this allow it to tell if its WOT or closed etc and can then go into the appropriate cycle i.e. idle....

2) To determine the rate of change of throttle, it does this by differentiating the voltage (look at an old L-Jetronic ECU and you can see the opamp setup that actualy does this!)....it can then see if you floor it or suddenly snap the throttle shut and provide fuel enrichment as required...
Title: Re: How does it work ?
Post by: Andy B on 08 May 2007, 12:02:47
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..... so will take it for the usual 100 mile trip to work and back today ........

 :o  :o How far? Is that a journey you make every day or just once a week and 'live' at work Mon to Fri? It makes my 40 mile round trip pale into insignificance  :-/
Title: Re: How does it work ?
Post by: amba on 08 May 2007, 12:20:19
I drive between 100/150 miles 6 days a week..sometimes 7 depending if I can keep the bank manager happy with just 6...that is why I like vauxhall omegas..great car/really comfy and most of the time realiable...anyway off to work now ..better find a petrol station first....and all for a "dollar"l
Title: Re: How does it work ?
Post by: Andy B on 08 May 2007, 12:55:51
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I drive between 100/150 miles 6 days a week..sometimes 7 depending if I can keep the bank manager happy with just 6...that is why I like vauxhall omegas..great car/really comfy and most of the time realiable...anyway off to work now ..better find a petrol station first....and all for a "dollar"l

That's some commute.  :o  You must be on first name terms with the staff at your local petrol station  ;)
Title: Re: How does it work ?
Post by: TheBoy on 08 May 2007, 18:22:20
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a real one, not a washing machine mechanic pretending to be one
But pretty good with Hotpoints IIRC ;) ;D
Title: Re: How does it work ?
Post by: Dave-C on 08 May 2007, 18:28:05
Quote
Quote
I was trained to take things apart to find out why they havn't broken yet.

Ahh, me too! Used to drive my parents mad when I was a lad. I wasn't as good at putting them back together again back then!

I can't accept anything unless I've dissected it and found out how it works...

Kevin

Get a job at Vauxhall's then !!!