Start up struggle

[someguy360]

Hi Guys.

Over the past 3 or so weeks the VS has been struggling at start up from cold start and warm starts.

On a cold start it will take around 4 seconds to fire and then it will shake at around 4-500RPM to the point of almost stalling for around another 4 seconds then will be perfectly fine from then on....if I leave it for half an hour or so it will do the same thing again.

Any ideas?

I have cleaned the IAC valve, PCV valce & TPS Sensor, Replaced the CAS, checked for vacuum leaks, checked error codes...inlet manifold gaskets were done around 2 months ago

Thinking it could be a bad injector, they all seem to be pulsing ok....and the car still runs like a dream its just this starting issue that has got me puzzled, only other possibility that springs to mind is the fuel pump.

I have taken advice off a US forum and disconnected the vacuum line off the fuel pressure regulator to see if fuel spits out which it doesn't (which is good).

Bit stumped.

Any help tracking down the issue would be much appreciated.

 

[tavrin]

Hi Guys.
I have taken advice off a US forum and disconnected the vacuum line off the fuel pressure regulator to see if fuel spits out which it does (which is good).

Oh? I was told the opposite. The vacuum line controls the pressure in the fuel rail. It should not have any fuel coming out from it. If it does then the diaphragm is possibly split causing it to run a little too rich on startup.

 

[someguy360]

Oh? I was told the opposite. The vacuum line controls the pressure in the fuel rail. It should not have any fuel coming out from it. If it does then the diaphragm is possibly split causing it to run a little too rich on startup.

Sorry my phone did auto correct lol...meant to say it doesn't spit out fuel which is good hahaha

 

[tavrin]

I have a very similar issue as well. Although mine is quite random and doesn't happen very often. When it does, it only really occurs when the motor is stone cold on cool mornings (I also noticed it needs to be left sitting for almost a day+). It will take a little bit to crank over. Once it starts the revs will sit at ~400rpm and feel as if it is about to stall. The problem vanishes after a few seconds and then runs flawlessly.

I think my injectors may be leaking ever so slightly and slowly floods the engine when left overnight.

One test which may work for you is to check your engine oil and see if it smells of petrol. Usually if the injectors are leaking a reasonable amount of fuel, it will leak down the bore and through the rings; right into the oil leaving a faint smell of petrol in it.

Hope that helps

 

[Jxfwsf]

fuel coming out of the vac line is only 1 way it can fail, it could be seized inside, change the fuel filter, try another reg (2nd hand from the wreckers would be fine to rule it out.

Get a bottle of injector cleaner and 3/4 of a tank of e10 and run it through when you're low on fuel next (good for cleaning out the fuel system, useless to run it all the time though)

 

[ONQ-247]

My car does the same. It's on struggle street when you start it cold of a morning, shakes/rattles/carries on until it has got a bit of heat into it and then it runs like a dream. I've also noticed that it idles like a bag of s**t when its warm.

 

[Wombles]

Someguy, how olds the bettery? How are your earth points?

 

[someguy360]

Someguy, how olds the bettery? How are your earth points?

Battery is just over 12 months old, ran a multi-meter over it, nothing out of the ordinary.

Earth points seem fine

 

[ONQ-247]

If the battery in the key is well passed its used by date, will the car have issues turning over? I've noticed that there are contacts on the ignition barrel which completes some sort of circuit to allow ignition to happen?

I replaced my battery a few weeks ago because I initially thought that the battery was the issue (after purchasing the car and not knowing it's history), but it's still got this hard start issue. Tested the Starter Motor for Amp draw as well and it was within spec.

 

[RX25SE]

Mine did this.

Leaky injector.

Before you shut of the engine pull the fuel pump fuse while holding the engine at a fat idle and wait for it to die.
Turn off ignition and replace fuse.

Leave over night and see if its any better in the morning.


Running the fuel pressure down before shutting it off will stop the injector from leaking./