Renault Clio 1.6 VVT noise and intermittent poor idle

[jkp2505]

I have a 2007 Clio Mk III with the 1.6 16V VVT engine. It's only done about 55000 miles and has been serviced yearly since I bought it 6 years ago.

For the last year or two I have been noticing a chattering noise from the engine, not very loud in general but very noticable when close to a wall or inside a garage. It begins a few seconds after starting up and does not go away when warm. I have also sometimes been hearing an unpleasent grinding noise when starting up after a long period without use, this goes away after a few seconds though.

Now recently in the last 6 months or so I have had problems with poor idling intermittently. It started off feeling like a very subtle and occassional misfire but now when it happens the car feels very rough and it can last several minutes at a time. Sometimes turning the car off and on again fixes it.

Two garages have looked at the car and found codes P0336 (camshaft tooth event) and P0346 (camshaft position sensor). One checked the cambelt and claimed it looked fine but suggested I go to a Renault specialist.

Researching forums I hear a lot of people describing similar symptoms when the dephaser pulley or solenoid goes bad. However, in my case the noise started long before the roughness and it doesn't really sound that bad - I don't think it's really worsened since the idling problem started. So I'm wondering if the two problems may not be totally related and maybe it's the camshaft sensor or wiring?

Finally I called another garage that deals mainly with Renaults and the guy wasn't all that helpful and said that basically anything could be wrong with it and he'd likely have to replace 3 or 4 parts to have any chance of fixing it, so would be over £850. One of the things he said was that he couldn't diagnose a bad camshaft sensor because it could be a crankshaft sensor problem instead and he therefore had no known reference point. Does that really make sense?

Thanks,

James

[bearman68]

Fair bit of experience with these engines, and it's almost certainly the dephaser pulley.
It's possible to log a camshaft error with this. Some of the earlier engines had a software writing error that would flag a camshaft fault even when there wasn't - mainly due to a very tight error window in the software - but by 2007, it should be sorted.
Best advice would be to change the belt (and other bits), and the pulley at the same time.
No harm in it as it's regular maintenance anyway.

Dephase pulley will knock really badly on cold start for maybe 5 seconds if it's knanckered.

[jkp2505]

Hi, thanks for the reply.

I tried searching YouTube for something similar to the chattering noise I mentioned and the closest example I could find on YouTube is this one: https://youtu.be/HKtdjSW8a6A

I am thinking maybe I may have a problem with the lifters in addition to whatever is causing the idle issue. So may not be worth trying to fix?

[jkp2505]

Took the car to another garage and he reckons it is indeed the dephaser pulley that’s the problem. It’s going to cost over £900 to fix (he’s replacing stuff like the aux belt and camshaft sensor at the same time since they are getting on and could also be part of the problem) but hopefully it will be worth it

[bearman68]

Don't bother with the camshaft sensor yet. I'd be very surprised if the dephaser pulley didn't sort it, and getting on a bit is I hope no reason to scrap things. (I really hope not)
If it's still showing camshaft timing errors after, then maybe, but not yet - it's simple to change anyway.

[Dynion Araf Uchaf]

jkp2505 said:

Took the car to another garage and he reckons it is indeed the dephaser pulley that’s the problem. It’s going to cost over £900 to fix (he’s replacing stuff like the aux belt and camshaft sensor at the same time since they are getting on and could also be part of the problem) but hopefully it will be worth it

I have a similar engine and got the belt, dephaser, pulley and water pump as well as gaskets for £200 labour and around £200 parts. Renault parts direct are your friends

[jkp2505]

Ouch, maybe I have been overcharged a bit then. Unfortunately I already agreed to have the work done as I didn't want to mess around any longer.

Would have preferred to have one of the cheaper/local garages to fix it it but this was the only one that claimed they had identified the problem. I already spent £200 total with other garages to do inconclusive diagnostics

[vtchequers]

jkp2505 said:

I

Now recently in the last 6 months or so I have had problems with poor idling intermittently. It started off feeling like a very subtle and occassional misfire but now when it happens the car feels very rough and it can last several minutes at a time. Sometimes turning the car off and on again fixes it.

Does the car shake at a stand still? Does it sound like it's sucking in air? Do the revs go down to around 400 and then the car starts shaking?
Could be a dirty Throttle body-

https://www.youtube.com/watch?v=02OAzLkbgwk&t=...

[jkp2505]

Thanks but hopefully the car has been fixed. I’m still waiting to pick it up

The garage has kind of messed me around a bit as they kept saying it would be ready the next day then it wasn’t. I told them several times I was going to pick it up this Saturday but then today they casually mentioned they wouldn’t be open

[vtchequers]

jkp2505 said:

Thanks but hopefully the car has been fixed. I’m still waiting to pick it up

The garage has kind of messed me around a bit as they kept saying it would be ready the next day then it wasn’t. I told them several times I was going to pick it up this Saturday but then today they casually mentioned they wouldn’t be open

Have they solved the problems?

[jkp2505]

vtchequers said:

Have they solved the problems?

The car’s been left with them all this time so I haven’t been able to test. Today when I again asked if it was fixed/ready they seemed to indicate it was but mumbled something about doing another test drive - not inspiring much confidence. I won’t be able to pick it up until next week

[vtchequers]

jkp2505 said:

The car’s been left with them all this time so I haven’t been able to test. Today when I again asked if it was fixed/ready they seemed to indicate it was but mumbled something about doing another test drive - not inspiring much confidence. I won’t be able to pick it up until next week

Hopefully they'd found the problem and fixed it to save face?

[jkp2505]

vtchequers said:

Hopefully they'd found the problem and fixed it to save face?

The car does seem a lot better but to me it still feels like it might be intermittently misfiring a little bit, I’m not sure. I’ve only used it three times since the garage fixed it and the first two times it seemed fine but then today it didn’t seem as smooth, particularly when moving slowly in traffic. I’m going to run some scans with my OBD scanner when I get a chance and see if there are any codes or values out of range

[jkp2505]

Car is now showing the following:

DF093 Downstream Oxygen sensor circuit Short-circuit to +12V
DF102 Alternator power available info Multiplexed network

Both are listed under the fuel injection category

I don’t think these were here before the work was done on it. I’m going to try clearing them and see if they return

[jkp2505]

According to the OBD tool the car is also showing nearly 50% fuel trim - from what I’ve heard that’s not normal at all? I’ve often thought I could smell petrol when near the car and the fuel economy seems to be even worse than it used to be so I was already wondering if it something was going on.

But maybe I’m just misinterpreting the figures, I don’t pretend to be an expert

[bearman68]

The O2 sensor is showing the heater has shorted to earth. That's maybe effecting the idle / running.
The 50% fuel trim is either the O2 sensor, or it may actually be a problem with one of the coils causing a misfire, ad the O2 sensor reacting badly (but predictably) to this.
I suspect CAN signal to the alternator will just clear and not come back.

I think you may have a coil intermittently failing.

[LimSlip]

jkp2505 said:

According to the OBD tool the car is also showing nearly 50% fuel trim - from what I’ve heard that’s not normal at all?

Certainly not normal, and overfuelling to that extent will quickly kill the catalytic converter.