How does the Variator Solenoid Control Valves work?

Would someone knowledgeable and kind enough to make the time share with us how the Variator Solenoid Control Valve works?

I think mine are failing (CEL P0024 Code) and signs of oil leakage after 36K miles and would like to learn how they work.

Thanks in advance.

Dan

 

They're basically a tube within a tube where the inner tube is connected to the crankshaft, and the outer tube is connected to the timing gear. The outer tube has holes drilled into it in which oil CAN flow. The assembly turns with each turn of the timing belt. The outer tube is sealed with rubber seals before and after the holes drilled into it.

There is an oil channel in the block that leads to the pressurized oil lubrication system of the engine. No oil flow goes into this oil channel unless the Variator Solenoid gets an electrical voltage that causes the electromagnet in its center to move upward, opening the channel (above 3600 RPM IIRC?). The oil then is allowed to flow in the channel. This oil flows through the channel/tube/passageway into one side of the variator, through the holes drilled in the outer tube. This "pressurizes" the space between the inner and tubes of the variator. When this happens a mechanical mechanism "rotates" the outer tube relative to the inner tube a few degrees. This is what changes the timing. When the solenoid valve closes, the oil pressure drops and the oil doesn't flow through the variator, and the timing goes back to normal.

The solenoid control valve is literally a solenoid consisting of an outer winding of wire, that when charged, causes an inner plunger to move up and down subsequently opening the channel between the holes in the variator solenoid so oil can flow. That simple. When the windings in the solenoid get older, the resistance can build or the plunger can get sticky with oil residue and not move as fast or efficiently leading to a code.

 

When that works, does it just go fully from one position to the other ? or does it go say to a mid position ?

 

On or off.

 

Thanks Curt and Brian for sharing great info. Now I know how they work.

Sincerely appreciated.

Dan

 

Ta, i was thinking that was the case- otherwise you would need some sort of sensor to tell you where it was.
Out of interest how many degree of cam timing does it move.

 

They aren't on or off but would behave as such if one applied 12v to the contacts. They are in fact a proportional flow type valve modulated by a PWM signal in order to regulate the degree of camshaft advance.

I'm very busy at the moment but soon I'll write up some info on their operation and testing - keep an eye on my project thread.

 

On a Ferrari 360? This will be an interesting dissertation.

 

OP owns an F430.

 

I am guilty of an assumption but some specificity in the question would be great.

 

Sorry for not being very clear. I have a 2006 F430 Spider.

I've read a few posts here about variator solenoids going bad, and throws a P0024 fault code.

It's not an easy part to change and parts are not cheap, about $900 each and there are 4 of them, two on each side.

I don't know much about what the part does and how it functions so I posted the question above hoping to learn something new.

Dan

 

If you have access to the plug for the solenoid on the top of the engine I'd check the resistance on the plug. Confirm that they are al equal. That *might* suggest that the plunger is sticking on the solenoid. I haven't priced it out as I have a 360 and the solenoids are outside the engine vs/ the 430 being under the valve covers... but perhaps if the error keeps popping up you might consider removing the variator solenoid and put it into an ultrasonic cleaner. Rationale being if there is some crud in it the cleaner might get it out. Not sure what price of this might be vs. replacing with new... .

 

Thanks for the info & suggestions curt.

I do have access to the connector plugs so I will check the resistance and compare all 4.

Dan

 

Hi Dan,
Could you get a reading that showed which one was defect? Did you end up cleaning them or changing?

 

@Bedrari, I very recently purchased Dan's car from a previous owner. I'm not sure if Dan changed the Variators during his ownership, but I pulled the same code, and my Ferrari mechanic confirmed that at least one is defective. I've decided to replace all 4, surprised there aren't more posts regarding this, as it's a common maintenance item I'm learning with the F430s. The parts for each Variator are still very expensive ($1k each), so something current/future owners should keep in mind.

FYI, the car recently hit 60k miles, despite the known wear items, it's still going strong.

 

I spoke with the local ferrari expert here. This issue is common but he said that the pressure inside the engine is high and overtime the gaskets around the cable that goes through the valve cover will leak oil that goes up the wiring and ends up in the contact.

I took the contact apart and cleaned it up, deleted the code and to this day the code havent came back