What fuel pressure tester?

Duncodin

Zorg Guru (III)
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Sep 8, 2021
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139
Location
Pontrhydyrun
Model of Z
Z3 M44
When I'm working near the car, bodywork etc. I often smell petrol. Also fuel seems to disappear much quicker than I'd expect considering the few miles I do at the mo. I think it's too much to be evaporation through the filler neck so a leak seems more likely. But where?

I'd convinced myself that I had a leak around the fuel filter coz that's part of the system I couldn't see.

Anyway. To cut a long story short. Today I removed the plastic tray/cover to get my eyes on the filter and pipes and all looks good under there.

I'm wondering if I should invest in a fuel pressure tester.

My understanding is that when the engine is switched off the fuel pressure should stay for quite a few minutes. But if there's a leak, or duff one-way valve, the pressure would drop off pretty quick (wouldn't it?)

Anyway. I thought having a gauge/tester would help me decide if I'm looking for a leak in the pressurised feed or somewhere around the tank?

Or what?

If you'd recommend getting a tester do you have any recommendation? They don't seem too expensive so even if I just used it once it'd pay for itself.

Thanks guys. (Sorry about the long post)
 
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Zephyr

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What engine is it?
Usually fuel smell comes after removing the injectors and fuel rail for service and you forget to replace or even put back the tiny o-rings that seal the lines.
it drips but due to engine heat it evaporates leaving that fuel smell. It also squirts when it starts as it builds pressure.
Fuel pressure gauges can deceive you as they can measure up to them and not after them.
 

Duncodin

Zorg Guru (III)
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Joined
Sep 8, 2021
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139
Location
Pontrhydyrun
Model of Z
Z3 M44
What engine is it?
Usually fuel smell comes after removing the injectors and fuel rail for service and you forget to replace or even put back the tiny o-rings that seal the lines.
it drips but due to engine heat it evaporates leaving that fuel smell. It also squirts when it starts as it builds pressure.
Fuel pressure gauges can deceive you as they can measure up to them and not after them.
Never removed injectors or done any work on fuel system.

As I said, I often get a smell of petrol when I'm stood near the car and fuel is disappearing when the car is stood a while.

I don't know what you mean when you said "measure up to them". Up to what?
 

Zephyr

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Up to the point that the meter is attached.
if you attach it at the regulator it will measure up to that point, if you attach it at the test slot up to the test slot.
Fuel smell may come after these points, such as injector o-rings, return line etc.
(Pic attached - pressure in this test was normal but the return line was rotten so there was the smell).
IMG_3277.jpeg
 

Duncodin

Zorg Guru (III)
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Joined
Sep 8, 2021
Points
139
Location
Pontrhydyrun
Model of Z
Z3 M44
I suppose what I'm asking is does anyone recommend any specific fuel pressure test kit. ie which one has the correct connectors/fittings for M44.

A few people say they bought a kit with a lot of different sized connectors but non of them fitted and they had to go buy another adapter. I don't need a dozen different connectors for a dozen different cars. Just a kit for my car.
 
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