Best tool to check the Fuel Pressure on ZT 1.8Ts.

[Abott10]

Simple request, what is the best measuring tool for this task.

Any advice or recommendations very welcome.

TIA.

[T-Cut]

I believe something like this is suitable:



Or perhaps a lock-on type to allow engine to run:



The workshop manual/RAVE says:
The 1.8Turbo rail pressure should be 4.45bar (64.5psi) at 13.5volts.

You might find this thread interesting: https://www.the75andztclub.co.uk/for...l+gauge&page=2

TC

[T-Cut]

I think the specified voltage will be important in measuring the absolute pressure. The battery may not provide that without the engine running, but since you plan to compare two pumps in different cars, the relative battery voltages between the two will be the thing. Maybe use the same battery on both if they're different

TC

[anddyy]

Machine mart do a nice fuel pressure guage for £41. This is the one I bought very impressed seems good quality and the quick release connections and extensions are handy for the 1.8 with the rail connection being buried under the throttle body.
https://www.machinemart.co.uk/p/clar...sting-kit-tes/


With the extension fitted it reaches the windscreen so you can see what's happening when starting.

[T-Cut]

Clicky here: http://www.ebay.co.uk/itm/449855-Fue...0AAOSw~gRVnRGj

Looks like the bee's knees for your job.

TC

[T-Cut]

I believe the 1.8T, like the KV6 fuel rail, uses a standard size Schrader (tyre) type valve.

TC

[minimutly]

Yes its a schrader valve. You can use ordinary fuel hose held on with a jubilee clip, but you need to unscrew the valve first.
I have a theory that most original fule pumps on these cars are starting to lose the will, its's very common to hear of issues, I have one here with that issue. Most car's fuel pumps last almost forever?

[Lovel]

Cant believe someone hasn't posted pictures of the Schraeder valve and gauge in place on the 1.8T before so here goes.

1.8T Photos L to R:
1. Shraeder valve behind inlet manifold at gearbox end.
2. Pressure gauge fitting in place.
3. Pressure reading ignition at position 2.
4. Pressure reading engine at idle. Pressure drops when revved perhaps to 2 Bar.

Link to thread with my experience when reading pressures on a turbo model. From post #6 onwards get a bit more interesting. What can be observed when comparing my earlier and different car readings is that the current readings taken today are quite a bit less. However todays reading were not taken while driving the car, as that perhaps would make some difference once the vacuum kicked in. If the rain stay off I might just try and obtain a reading while driving later on.
https://the75andztclub.co.uk/forum/s...+pump+pressure

[Lovel]

OK here are the results after a little test drive (for any HSE wallas my Granny took the photos and the wipers were removed).

Car is running A1 on the 160ps MG tune and clean thrash up to rev limiter.

Photo L to R
1. Initial drive off pressure reading, blurred but is around 3.4 Bar about 3,000rpm at 50mph.
2. After about a mile or two, built up to 4.1 Bar about 3,000rpm at 50mph.
3. At idle after a good stretch of its lungs 4.1 Bar.
Saw a max of about 4.5 Bar at full revs.
4. At idle just returned car into garage 4.3 Bar.

[SD1too]

Gary; excellent research and evidence, thank you.

I did not expect 'regulated' fuel pressure to vary with engine speed. Why should it?

But then, does it? 4.5 at full revs then 4.3 at idle? It would seem that pressure readings at the schrader valve are anything but reliable data for fault diagnosis.

Simon