Problems with valve timing Sport172.

[Falk]

Yesterday i experienced a sudden lack of power, also the noticeable powerboost at 5krpm was gone. One can hear a strange noise coming from the variable cam timing mechanism when engine is hot at tickover...? Has anyone had this type of problem?

Can I find a description of the timing function somewhere on the web? I would like to know a bit more before I take the car to the dealership tomorrow.

The car has only 3000km on the dial carefully driven by my wife... The idea was to get a warranty/goodwill repair.

 

[viceroy]

Quote: Originally posted by Falk on 18 August 2003


Yesterday i experienced a sudden lack of power, also the noticeable powerboost at 5krpm was gone. One can hear a strange noise coming from the variable cam timing mechanism when engine is hot at tickover...? Has anyone had this type of problem?

Can I find a description of the timing function somewhere on the web? I would like to know a bit more before I take the car to the dealership tomorrow.

The car has only 3000km on the dial carefully driven by my wife... The idea was to get a warranty/goodwill repair.





what does this sound like...just out of interest?

 

[Falk]

Its a knocking sound, as if moving part has lack of tension. Maybe the camshaft is more or less freely moving to its extreme positions. (Just guessing here as I dont know how this thing works. Oil pressure? Electrically triggered?)

The noise gradually disapears when revs go up. Its worse when engine is warm. Almost gone when cold.

Would have been interesting to see an exploded veiw of the timing mechanism, or description...

According to the mechanic this was not a common problem. (But I guess they tell you the same story all the time...)

 

[Falk]

Quote: Originally posted by Falk on 18 August 2003


The car has only 3000km on the dial ...

SORRY, typing error. Should read 33000km...

 

[BenR]

Failure of the VVT system is not common at all.

its simple cam phasing device which advances the inlet cam 16 deg in a single go. When above 1500rpm the VVT is activated, simple as that. When off the throttle its depahsed again, at idle its dephased. Simple emissions and idle smoothness reasons. Its operated via oil pressure and there is a simple plunger on the left hand side of the cam cover, this activates with a 12V current and allows oil in a gallery to the actuator.

If your plunger then it should be easy to fix, but it sounds like the actuator......still all should be warrenty work though.

 

[Falk]

I did have a look myself under the plastic cover...

I think I understand the basic function now. Must be a two way plunger solenoid valve sending oil pressure to the phase actuator either phase shifted or not. You say its always advanced over 1500 rpm?? How come the kick at 5krpm is gone now? Something must shift at 5krpm when its working properly. Has anyone actually checked the operation of the solenoid valve? On/Off state vs. rpm, engine load, watertemp, lambdareadings etc...?

What if my oilpressure is (almost) gone. Would the actuator unit rattle?? Oil pressure light goes off normally though. Running on fully synthetic 10w60.

(Sorry for crappy english, not really used to write in english. Better than Swedish for you guys though, I guess...)

 

[BenR]

that kick is just the cam comming on......the VVT is actuated from just above idle and beyond a certain throttle position. The kick wont be there as your running about minus the 16 deg advance that you would normally have.

Oil pressure cna affect it yes.

 

[Falk]

This morning I went to the office in the Clio. No strange sounds when cold. It seems as the rattling nocking sound is there only when the engine is really hot. As long as it sounds normal the power output seems to be ok. I think Ill have to convince Renault to check the oil pressure at idle when really hot... (during summer im using an excellent quality 10w60 fully syntethic oil, so I dont think the oil quality is the problem)

> BenR, maybe you can answer som more questions...:

What is the working voltage of the soleniod valve? 12V? I checked the resistance, approx 10ohms. How is it logically connected to the ECU? Will the ECU give a high signal or connect to ground? What is the normal state? Is the cam advanced when voltage is applied?

It would be interesting to check the position of the inlet cam with a strobe light...

 

[BenR]

im not sure how it is activated exactly, dunno whether its grounded or a straight voltage applied, never checked. And i only tested with a 12V application..........try it when at idle. connect up an LED and apply rpm, the light will come on when VVT is activated. Apply a striaght 12v current to the plunger at idle and it should, if working, idle very badly and sound horrible.

The normal state is de-phased.........when voltage is applied its advanced yes.

Check the timing by all means, but if you need to timing info i have it.

Your oil weight might have something to do with it, try a 5w40 like its meant to run on.

 

[Falk]

Quote: Originally posted by BenR on 19 August 2003


im not sure how it is activated exactly, dunno whether its grounded or a straight voltage applied, never checked. And i only tested with a 12V application..........try it when at idle. connect up an LED and apply rpm, the light will come on when VVT is activated. Apply a striaght 12v current to the plunger at idle and it should, if working, idle very badly and sound horrible.

The normal state is de-phased.........when voltage is applied its advanced yes.

Check the timing by all means, but if you need to timing info i have it.

Your oil weight might have something to do with it, try a 5w40 like its meant to run on.

Thanks for this info!

Today I took the car to the Reno garage where a bunch of guys had a really close look at it for a long time. Guess what, we couldnt make the engine show the bad symptomes. It idled perfectly quiet and blasted like a turbine to the revlimit. I went 160km/h up and down the motorway and threw it around some twisty backroads to really get the oiltemp up. Perfect function. Isnt that typical...

Well, they are now going to check with Reno support dept to try and find some explanation for this. Very professional attitude from the guys at SydUpplands Bil. They confirmed what you wrote about the function and showed me some litterature, drawings etc. As soon as the noise/malfunction is there again they told me to bring back the car right away.

to be continued

 

[BenR]

its not typical, Renault install a reciever device in the car, hidden away behind the bulkhead that stops faults from occuring near a dealer (2km range).

Did they check the oil pressure manually?

 

[Falk]

Quote: Originally posted by BenR on 20 August 2003


its not typical, Renault install a reciever device in the car, hidden away behind the bulkhead that stops faults from occuring near a dealer (2km range).

Did they check the oil pressure manually?

No they did not.

If/when the problem occurs again they will check it with an external mechanical oil pressure gauge.

 

[BenR]

righto........

 

[Falk]

Quote: Originally posted by Falk on 19 August 2003


to be continued

Well...

Today I went to a trackday at Bjorkvik Ring. No problems what so ever.

I did top up the oil level to a few mms above the maximum mark on the dip stick. Maybe the oil-surge theory due to R-tyres etc. was correct after all.

BTW, the ClioSports ruled the track.

A few pics:

http://hem.fyristorg.com/cednert/Peugeot.%20Renault/http://hem.fyristorg.com/cednert/Peugeot.%20Renault/