The Camaro Club (UK)

A couple of easy checks for known problems because it sounds like you are getting fuel settling in the engine which is being cleared at start up, hence the smell.
Pull the vacuum line off the fuel pressure regulator and have a sniff. Smell petrol?, then the regulator is leaking and pulling raw fuel into the manifold via the vacuum line.
Next one will need a fuel pressure gauge.
With the gauge attached turn the ignition on, this will start the fuel pump for a few seconds and the fuel pressure should rise to about 40 PSI. If it's a lot more you have a broken regulator, a lot less a broken regulator or a bad fuel pump/partially plugged filter.
Assuming it's around 40 PSI watch the needle. If it drops quickly, you have a leaking injector, or multiple leaking injectors.

Hi Neil,

Thanks for laying out those diagnostics, i'll start working on them. Got an o2 bung, just need the sensor, so will place an order soon for that and a few other bits. I'll try and figure out the location based on Jon's comments below, may already be a place for it in the manifold, haven't had enough time to look into it yet.

I have an adjustable fuel regulator, it's just not installed (still with the guy, need to pick it up) so that could help with part 1 of the fuel diagnostics. I have also have a replacement fuel filter, just need to fit it. This is for the one that sits on the drivers side, under the rear seat location.

I will need to get a fuel pressure gauge to help with the final part that you mention. It might even be something like a leaky injector as you say.

What's interesting is that in the morning, the car starts straight up, cranks for maybe a second, but fires and idles straight away. When leaving work, after it being sat for a shorter amount of time compared to overnight, it cranks for about 4 or 5 seconds before it fires and idles. As if it's in 'clear flood mode'.

So maybe there is fuel getting in somehow. The smell is constant, even when parking up after a long drive so you maybe onto something outisde of the o2 sensor part.

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