Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: olm on 04 October 2021, 10:06:43

Title: Firts cold start failure
Post by: olm on 04 October 2021, 10:06:43
Hi, It's been a while since the first cold start didn't turn on, it doesn't matter if I insist, instead, on the second attempt it starts immediately. Any ideas? Some sensor?
Tnahks
Title: Re: Firts cold start failure
Post by: Andy B on 04 October 2021, 13:20:21
my first thoughts would be the coolant temp sensor ie the one that talks to the engine ECU rather the sensor for the temp gauge.  :-\
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 04 October 2021, 15:06:23
Fuel pump, Pressure regulator or a leaky injector.

What happens if you turn the key to position 2 then back to off one or two times before actually cranking?

If it fires instantly then you have a fuel delivery issue.

What temperature are you considering a cold start?
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 04 October 2021, 15:20:24
my first thoughts would be the coolant temp sensor ie the one that talks to the engine ECU rather the sensor for the temp gauge.  :-\
In my experience, failure of this sensor defaults to - 40°C. Cold starts are fine, but hot starts cause it to flood as soon as the pump runs. Gives similar symptoms to crank sensor, but if you pull the fuel pump fuse, it will fire of the residual in the rail ;)
Title: Re: Firts cold start failure
Post by: olm on 06 October 2021, 15:27:21
my first thoughts would be the coolant temp sensor ie the one that talks to the engine ECU rather the sensor for the temp gauge.  :-\

That happened to me in another car, but I do not know if it is possible in the omega too, hence my question
Title: Re: Firts cold start failure
Post by: olm on 06 October 2021, 15:31:44
Fuel pump, Pressure regulator or a leaky injector.

What happens if you turn the key to position 2 then back to off one or two times before actually cranking?

If it fires instantly then you have a fuel delivery issue.

What temperature are you considering a cold start?

The same thing happens.
Arranque en frio me refiero a temperatura ambiente tras una larga parada, generalmente de un dia para otro, cuando necesita usar el starter
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 06 October 2021, 16:21:02
Sunrise air temperature in Maspalomas is 21°C...

Hardly 'cold'.

Also, you didn't answer my question... If you cycle the key a couple of times, does it start instantly?
Title: Re: Firts cold start failure
Post by: olm on 07 October 2021, 13:04:18
Sunrise air temperature in Maspalomas is 21°C...

Hardly 'cold'.

Also, you didn't answer my question... If you cycle the key a couple of times, does it start instantly?

No, does the same
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 07 October 2021, 13:09:02
Hi, It's been a while since the first cold start didn't turn on, it doesn't matter if I insist, instead, on the second attempt it starts immediately. Any ideas? Some sensor?
Tnahks
You mean this "the same"?

Use a tyre gauge and check the fuel rail pressure before the first start.

Report back ;)
Title: Re: Firts cold start failure
Post by: olm on 06 November 2021, 11:12:27
Well, I have not yet been able to perform the measurement but currently it starts well the first time. Saying that now I only run on gasoline, I don't use LPG, could that have something to do with it
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 06 November 2021, 11:34:41
Now you mention LPG ???
Title: Re: Firts cold start failure
Post by: olm on 06 November 2021, 14:04:34
Now you mention LPG ???

I understand what influences the use of lpg? Do not mention it at the time because the start is on gasoline.
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 06 November 2021, 15:22:29
It doubles all the potential trouble spots and introduces all sorts of variables into the cooling and electrical systems...

LPG is only as good as the quality of the parts and the quality of the installation.

It is, therefore, an important part of the diagnosis, especially with regard to poor starting and running.
Title: Re: Firts cold start failure
Post by: olm on 06 November 2021, 16:02:52
It doubles all the potential trouble spots and introduces all sorts of variables into the cooling and electrical systems...

LPG is only as good as the quality of the parts and the quality of the installation.

It is, therefore, an important part of the diagnosis, especially with regard to poor starting and running.

So I understand that I should tell the lpg installer?
Title: Re: Firts cold start failure
Post by: Doctor Gollum on 06 November 2021, 16:11:51
Unless you have the diagnostic kit for the LPG ecu...

But, each installation and each installer is different... A good system fitted badly will be more trouble than a bad system fitted well.

There are several members here with direct experience of a variety of systems who might help point you in the right direction, but it ultimately boils down to how it is fitted.
Title: Re: Firts cold start failure
Post by: olm on 06 November 2021, 16:23:14
Unless you have the diagnostic kit for the LPG ecu...

But, each installation and each installer is different... A good system fitted badly will be more trouble than a bad system fitted well.

There are several members here with direct experience of a variety of systems who might help point you in the right direction, but it ultimately boils down to how it is fitted.

Ok, I will comment to them then. :y