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[Dutch924-racer]

I have a problem with my 924 NA (EU), the system pressure is 4.8 bar which is fine, but the control pressure is also 4,8 bar.

What I did already:

- I changed the wur with another one, no difference (still 4., but the condition was unknown.
- Tested the gauge set one my 931 and it works fine.
- To be sure I turned around the fuel lines of the gauge set but no difference. I hooked up like in the manual, so that can't be the issue.

What could be the problem ?
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937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller

[Fasteddie313]

As long as the valve was open it should read control pressure. You say you tested the gauge on your 931 and the gauge is confirmed working correct?

The fuel feed to WUR line from the FD to the WUR could be plugged between your gauge and WUR.
The return from WUR fuel line could be plugged between the WUR and FD.
The FD could be plugged between the return from WUR port and the return to tank port.

Take the WUR fuel feed and return lines off the distributor and WUR and blow them out with an air compressor.
If that doesn't fix it then pull the system pressure control plunger mechanism out of the FD and inspect it for gunk. Blow in the port where the WUR return line comes into the FD.

This is the 931 one but should be similar for the na..


I don't think you have a frequency valve in euroland but if you do it will be on the same return circuit as the WUR, its return Ts back into the WUR return line.


If you accidentally installed your gauge on the cold start valve line instead of the WUR line it would just look like system pressure as you describe so maybe their is a slight chance you did that..
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80 Turbo - Slightly Modified

[Johann]

When you read no differente between an open and closed valve, I think it is fair to say your WUR is no longer working. In my experience this means that the shaft is rusted and can no longer move freely, making it impossible to push down on the diaphragm.

[safe]

[Dutch924-racer]

Problem solved !

Thanks Fasteddie313, I replace the injection system on this 924 and accidentally swapped the cold start fuel line with the one for the WUR. I discovered it because you mentioned I possibly put the test gauge on the cold star valve

Also thanks to Johann, the WUR was indeed also the problem, the small holes where partly clogged, so I dismantled it fully for a goed clean.
_________________
937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller