General Ducato x250 power steering pump problem

[Jacaranda]

I am having difficulty turning the steering wheel when stationary or moving very slowly. The steering wheel is very stiff until it is moved to around 90 degrees, and then it suddenly becomes easy to move, presumably as the power steering starts to work? Does this mean I need a new steering pump, or is there possibly another solution like a valve or similar to check out first to fix the problem.

Thanks!

 

[digger58]

Is the oil level OK? any leaks?

 

[rolopolo]

What year is your van?

There was an early recall on power steering, weather yours is in those dates, I suspect pump wear, fluid loss or contamination, as above, check for leaks, fluid level, quality, maybe change the oil as, again no idea on age or mileage, it may just need new oil

 

[Jacaranda]

Hi rolopolo, thank you for the information. My van is a 58 plate with 183,000 miles on the clock, not within the dates for the recall. The fluid has been changed and there are no leaks. Since then, the problem is intermittent, one day working fine, the next day, as bad as ever. Do you know if there are any filters on the steering system that we could check out. Because the problem comes and goes, we are thinking it might not be the pump. Or maybe a faulty pinion valve?

We have tried to find a diagram of the powered steering system on line to see what the problem may be, but no luck finding anything so far.

 

[Jacaranda]

Hi digger58, the fluid level is fine, has been renewed, and no leaks. Problem now intermittent.

Thanks.

 

[Jacaranda]

Since starting this thread, the problem remains with intermittent stiff steering, however it tends to become worse after using the van for over 30 mins. I have noticed there is an electrical plug going in to a cylinder shaped part on the pinion valve. Does anyone know if this is a solenoid switch? If so, could this cause the problem if it were faulty/sticking?

 

[rayc]

Since starting this thread, the problem remains with intermittent stiff steering, however it tends to become worse after using the van for over 30 mins. I have noticed there is an electrical plug going in to a cylinder shaped part on the pinion valve. Does anyone know if this is a solenoid switch? If so, could this cause the problem if it were faulty/sticking?

The solenoid appears to be important and is operated by a signal which varies with road speed.

 

[Jacaranda]

Hi rayc,
Thank you very much for the information. Would you know the voltage reading that should be supplied to the solenoid when the van is standing still?

 

[CDK]

Fiat uses PWM (pulse width modulation) for most solenoids.
At zero speed the solenoid gets 12VDC. The battery voltage is always present: the rapid on/off modulation is done at the negative (ground) side. To properly observe the pulses you need an oscilloscope.