No gearbox hydraulic pressure… so sat in a car park and not going anywhere.

[Jezbraker]

So this happened a few days back - and by the time I’d got home, got trailer back to car to recover, it started fine and I drove it onto the trailer.

this time I have my launch with me… I can see the relay shows on when I open the door but the hydraulic pressure that was measuring 40 to 50 has dropped to -2. Most odd.

any ideas what I can jiggle?

 

[safrane]

Non return valve?

 

[Jezbraker]

Well after about 30 mins of being stuck the gear actuator test started to work - with ignition on I could get it to select a gear with the launch actuator jobbie and the pressure started to show up again..
still wouldn't start. but about ten mins of flipping through gears the key turn made her purr again and have no made it home.

So what are the conditions for allowing start up? door closed, bonnet close, foot on brake, neutral selected?

Funny how these seems to occur after a good run out when everything is hot.at home in the garage it springs into life first time every time.

first time i shifted to neutral sitting in traffic... wouldn't select first - i switched off and on again it got first (but no more) until I got safe then off again and wouldn't start.
this time parked at post office came ad when i got through the queue of euromillions hopefuls and back to the car wouldn't start.

 

[Oneball]

Have you checked the fluid level?

 

[Zep]

If the fluid is low there is a level sensor. My money is on pump or relay, classic symptoms.

 

[safrane]

Had my original pump replaced this year at c55k miles... amazed how much faster the new one runs in comparison.

Also had the lines and relay done too at SI.

 

[Jezbraker]

So pulled the boot floor and while doing so can here the relay clicking on and off every couple of mins. Pressure reading -2 again. Launch shows this as well…



fluid level seems good (and yes see a sensor as you say)

is the hydraulic pressure sensor built into the pump? If so I guess I’m shopping for Alfa pumps

Some connection blocks are free (tin worm on the little metal mounts) but gave everything a good jiggle and no change.

 

[Zep]

is the hydraulic pressure sensor built into the pump?

No, it’s at the top of the valve block, behind this pipe.

 

[tulit]

So what are the conditions for allowing start up? door closed, bonnet close, foot on brake, neutral selected?

Plus clutch position sensor indicating it is disengaged (which requires hydraulic pressure).

You say you hear the relay kicking on. Do you hear the pump?

If not disconnect the pump at the valve body and measure at that connector with a multimeter. Do you see 12V when the relay clicks on? If yes, your pump is likely shot. If not, check the contacts on the relay. I've had a few wiring harnesses now that the output of the relay doesn't make contact (wiggling the wires going into the relay base temporarily solve that). If still no luck, replace the relay.

 

[Jezbraker]

So update on this one…. The pump was looking pretty corroded so I imagine would be the original so decided to just replace it (and the relay) with the Alfa alternatives… done about 100 miles since and no further issues with the hydraulic pressure.

while I’ve been mucking about underneath her this…

Has been replaced by this…


she is sounding considerably more super car!

 

[Jezbraker]

Certainly not going to be inconspicuous

I guess what I really need is gransport back boxes to be able to turn the volume down a touch on demand... going through little narrow roads in town one does feel a little bit like a kid that's chopped of the exhaust on his corsa!

Sounds awesome when giving beans though!