I've found the source of a top end rattle when the engine is warming up. If I disconnect the nearside VVT solenoid connector the rattle disappears, when I re-connect it the rattle stays gone for the rest of the day.

How do these solenoids work and are they easy to change?

And where are they?

 

Got a pic?

There is one on the back of each cam, at the rear of the engine and they advance the timing in a certain rev range. The problem is I dont know exactly how they work. I know there is a spring at the other end of the cam. I guess only tech heads need reply.

The VTC system varies the intake valve opening and closing time by managing the cam phase. The system is driven by oil pressure controlled by the VTC solenoid. As well as maximising useable power and torque when required, the VTC system contributes to improved engine idling stability and lowered fuel consumption.

 

The design of the sprocket is such that the cam is mated using a short worm gear that allows a very minor degree of rotation between the camshaft and the sprocket.

The state of the VTC system is determined by the ECU and implemented using solenoid valves that either plug up or open the oil drain ports on the back of the intake cams.

In the default (OFF) position, the drain ports are open, allowing oil to flow fairly freely through the intake camshaft and sprocket as part of the normal circuit. The VTC springs hold the worm gear fully extended, locking the camshaft to the sprocket in the OFF alignment.

When the ECU signals the VTC system ON, the solenoid valves energize and their plungers plug up the oil drain ports on the camshafts. With no exit drain, oil being pumped into the cams and sprockets builds up pressure. This hydraulic pressure pushes against the VTC springs, driving the internal worm gears up their paths (much like turning a nut to advance it along the threads of a bolt), advancing the orientation of the camshafts by a few degrees with respect to their sprockets.

When you hit ~5500rpm, or when you release the throttle, the ECU signals the solenoids OFF, opening the oil drain ports and relieving the hydraulic pressure. The VTC springs drive back the worm gears, returning the camshafts to their previous timing orientation.

 

In short your VTC spring which is located within the intake pulley needs replacing :cool:

 

Hope this helps

 

Ryan

Wow.Thanks man.

We could do with more posts of this quality on here.

Do you sell the springs, how much, and how difficult etc.

Wow.Thanks man.

We could do with more posts of this quality on here.

Do you sell the springs, how much, and how difficult etc.

 

easy peasy just remove the two top cam covers and undo the 4 small bolts holding the plate on to the face of the intake cam then just pull out the old spring and replace with new ones, just don't forget to put the little rubber O-ring back on

 

PM me your address and I will send you out a couple FOC Colin

 

Regarding the post I wish I had more time on the board to post good technical posts but I just don't have as much time on here as I would like anymore

 

Ryan

easy peasy just remove the two top cam covers and undo the 4 small bolts holding the plate on to the face of the intake cam then just pull out the old spring and replace with new ones, just don't forget to put the little rubber O-ring back on

 

PM me your address and I will send you out a couple FOC Colin

 

Regarding the post I wish I had more time on the board to post good technical posts but I just don't have as much time on here as I would like anymore

 

Ryan

 

 

oh master

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

wheres the payrise then :smash:

oh master

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

wheres the payrise then :smash:

 

Your mrs had it in kindness last weekend :shock: :rofl: :rofl:

You've already got all my details. I've had various bits off you.

I really appreciate it by the way and its a shame you can't post more often.

It can be difficult to get accurate advice as the people you want to speak to are not always on-line.

I'll call you tomorrow just to confirm address etc.

You've already got all my details. I've had various bits off you.

I really appreciate it by the way and its a shame you can't post more often.

It can be difficult to get accurate advice as the people you want to speak to are not always on-line.

I'll call you tomorrow just to confirm address etc.

 

No probs always happy to give advice over the phone if required

No probs always happy to give advice over the phone if required

 

 

yeh colin to get hold of ryan its 0845 27 27 27 ask for fat slags :p

yeh colin to get hold of ryan its 0845 27 27 27 ask for fat slags if I am not available I go by the name of gregorina :p

 

LMFAO I feel at least 3 heater matrix's for you next week peck!! :( :cool:

LMFAO I feel at least 3 heater matrix's for you next week peck!! :( :cool:

 

 

*****x :cry:

quick question which connector can you disconnect to test if it is the vtc springs as mine is a little rattly

bump LOL

basically why im asking is im getting a rattle at the back of the engine and i suspect the vvt vtc springs at the back of the cams. would the springs cause this and which connector do i disconnect to see if the rattle stops

 

cheers

gaz

The springs are at the front of the cams, behind the timing belt cover.

You can trace the connectors from the vtc solenoids at the back.

You can just about see them at the rear of each head.

Its easier with a consult as you can turn them on or off.

I still get this problem intermitantly and am starting to think my lifters are worn.

The springs are at the front of the cams, behind the timing belt cover.

You can trace the connectors from the vtc solenoids at the back.

You can just about see them at the rear of each head.

Its easier with a consult as you can turn them on or off.

I still get this problem intermitantly and am starting to think my lifters are worn.

thanks matey for the reply