Omega Owners Forum

Chat Area => General Discussion Area => Topic started by: JamesV6CDX on 22 July 2007, 18:09:57

Title: Emissions light sorted !
Post by: JamesV6CDX on 22 July 2007, 18:09:57
Spent a few mins re-arranging my Vacc and breather pipes this morning. I had the evaporator vacc feed wrong, and the camcover breather wrong.

Since correcting these - emissions light has gone out ;D
Title: Re: Emissions light sorted !
Post by: JamesV6CDX on 22 July 2007, 18:10:59
Strange, when assembling the engine I could not get it quite right...(I even asked Mark to take a look).. however today, it took me less than 5 minutes to see what was up.

Shows what looking at things with a clear head can do!!
Title: Re: Emissions light sorted !
Post by: TheBoy on 22 July 2007, 18:25:22
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Strange, when assembling the engine I could not get it quite right...(I even asked Mark to take a look).. however today, it took me less than 5 minutes to see what was up.

Shows what looking at things with a clear head can do!!
Aye, if I can't get my head round something, stopping for a cuppa and/or sleep on it, its usually clearer afterwards :y
Title: Re: Emissions light sorted !
Post by: megaomega123 on 22 July 2007, 18:42:27
Isn't it so enlightening when you spot it  :D
Title: Re: Emissions light sorted !
Post by: Taxi_Driver on 22 July 2007, 18:45:17
Well done  :y

Im suprised you didnt get probs on lpg with switching to petrol around town.

That vac pipe to the evapourator controls how much lpg gets fed into the inlet.....no vac and its max amount of gas.....which isnt a prob if you floor it everywhere....but poodle about town and the pressure builds up too much, ecu notices and thinks theres a fault and switches to petrol.
Title: Re: Emissions light sorted !
Post by: JamesV6CDX on 22 July 2007, 22:05:26
Are you saying then, that the more you rev the engine, the more Vacc goes to the evaporator?
Title: Re: Emissions light sorted !
Post by: Taxi_Driver on 22 July 2007, 22:40:09
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Are you saying then, that the more you rev the engine, the more Vacc goes to the evaporator?

Well. from ive found out....no vac to evapourator means full gas pressure....lots of vac means less pressure
Title: Re: Emissions light sorted !
Post by: Martin_1962 on 22 July 2007, 23:32:17
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Are you saying then, that the more you rev the engine, the more Vacc goes to the evaporator?

Well. from ive found out....no vac to evapourator means full gas pressure....lots of vac means less pressure

I had a breather pipe split and this over pressured my Romano injectors - which don't like too much pressure but are quiet and reliable.

No vac is full flow!
Title: Re: Emissions light sorted !
Post by: Kevin Wood on 23 July 2007, 09:55:53
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Well. from ive found out....no vac to evapourator means full gas pressure....lots of vac means less pressure

Vacuum is a good indicator of engine load, and this is why it's used to control LPG delivery (and fuel injection on many cars, although the MAF does that job on an Omega).

Imagine an engine idling (very little load). The engine's trying to suck air in at roughly its' swept volume every stroke but the throttle is limiting this to very much less. The result is that a vacuum builds up in the inlet manifold.

Gun it away from the lights at full throttle and the throttle valve is wide open, and presenting very little resistance to the path of air into the engine. The manifold vacuum collapses and you have pretty much ambient pressure in the inlet manifold.

So, the LPG system will indeed deliver more gas as the vacuum disappears.

This is also why the vacuum systems that control the multirams and other gadgets have those pesky reservoirs that keep breaking - because, under full throttle conditions, there is no vacuum from the engine, so they store a little vacuum to be used in such circumstances. If you can store a vaccum, that is :-/ :-? :-X

Kevin