Zafira Engine Noise

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rcwilko
Posts: 33
Joined: Sat Sep 26, 2020 1:53 pm

Re: Zafira Engine Noise

Post by rcwilko » Thu Jan 14, 2021 4:43 pm

The is for the correction
Would that change the possible diagnosis? More likely to be timing related?

It was running on low oil for a few months, in the min area of the dipstick

Perhaps this has contributed to the problem
(When I purchased it, the service book was signed with a new service and the onboard computer oil level updated to 100% but only a couple of months later did I realise that it the oil hadn’t actually been changed)

Redman
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Re: Zafira Engine Noise

Post by Redman » Thu Jan 14, 2021 6:05 pm

No I don't think it would change the diagnosis.
Did you try removing oil dipstick whilst engine running?

rcwilko
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Re: Zafira Engine Noise

Post by rcwilko » Fri Jan 15, 2021 2:36 pm

Hi Redman

Had a chance to have another look today.

It seems to be the plastic lid that rattles when the engine gets to a specific temperature.

In new the video below i started the car from cold, and it took around 8.5 mins for the sound to return!

I then pressed on the plastic lid (the bit that says eco-tec) and the rattle totally stops!

A mechanic had ‘opened up’ the lid to have a look when we were getting the repeated p0011 code.

Do you think that the casing hasn’t been put back on properly? I can wiggle it about a bit when then engine isn’t running.

Also, what are your thoughts as to why it takes over 8mins for the rattle to appear. Is it because as the engine warms up it vibrates at different rates?

Do have a look at the video below if you can. The rattle appears just after 8mins

Thanks again for all your help!


astraowner
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Re: Zafira Engine Noise

Post by astraowner » Fri Jan 15, 2021 4:34 pm

Are all the studs that the lidt clips into there ?

Are all the rubber grommets that gets pressed down onto the studs there ?

If yes, you need to look for something that might rub on the cover on the underside...If this has been going on for some time, chances are, you will find a spot that has been rubbed, on the back of the cover.
2016 Astra K 110HP, Opel Eye camera, front and rear parking sensors, dual zone climate control and heated front seats, sight and light pack.

rcwilko
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Joined: Sat Sep 26, 2020 1:53 pm

Re: Zafira Engine Noise

Post by rcwilko » Fri Jan 15, 2021 4:47 pm

Thanks for reply, Astraman, will check that out

Was also wondering - what do you make of the startup noise? A mechanic (who I don’t think was a Vauxhall specialist) said that he didn’t like the sound of the first second of start up - said it might be timing chain ‘slap’?

Is it normal for the first second of cold startup (which was the case in the video) to be slightly louder?

Redman
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Re: Zafira Engine Noise

Post by Redman » Fri Jan 15, 2021 5:29 pm

Hi
Again have you tried pulling the dipstick out with the engine running and warm ?.
That cover allows access to the coil pack and spark plugs. There is also a valve under there that is part of the crankshaft ventilation system and they do go faulty. So please illiminate that

rcwilko
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Re: Zafira Engine Noise

Post by rcwilko » Fri Jan 15, 2021 7:48 pm

Sorry Redman, knew there was something else I meant to do. Will try that tomorrow.

What do you make of the rattle on start up?
Is the timing chain tensioner taking too long to pressurise? You hear some horror stories of rattles leading failure on the chain system.

Redman
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Re: Zafira Engine Noise

Post by Redman » Fri Jan 15, 2021 8:23 pm

rcwilko wrote:
Fri Jan 15, 2021 7:48 pm
Sorry Redman, knew there was something else I meant to do. Will try that tomorrow.

What do you make of the rattle on start up?
Is the timing chain tensioner taking too long to pressurise? You hear some horror stories of rattles leading failure on the chain system.
It does sound like chain tensioner lag, soon goes though. The engine sounds quite normal after that as you say up until the 8th minute. If it were just a case of a loose rocker cover panel it would do it also on fast cold idle imho.

Modern engines use oil to do so much aswell as lubricating. The oil has to lift the hydraulic valve lifters to optimum, drive the vvti via solenoids, tension the timing chain from a cold start etc. If I am not mistaken there is some sort of oil non return valve up there, which can pass over time. So keep oil changes top priority and monitor the start up noise over time.
The cover maybe rattling due to a faulty rocker cover pcv valve. So crankcase positive pressure
( piston blowby pressure build up ) is venting through it, rather than going fully through the breather system properly and into the engine to be burned. I may well be wrong but no harm done in illuminating it. Hence see if you have crankcase suction at the dipstick.

rcwilko
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Re: Zafira Engine Noise

Post by rcwilko » Fri Jan 15, 2021 8:32 pm

Really appreciate the advice and explanation

I’ll get it out for drive in the next couple of days. Might not be able to tomorrow. Thanks again!

Redman
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Re: Zafira Engine Noise

Post by Redman » Mon Jan 18, 2021 7:22 am

Here is a video of the particular valve failing. It is an American cruze which is Gm and your engine type.
You can also see how easy it is to remove the aesthetic cover, by pulling it off, so you can check out the fixings on it at the same time. So hopefully you can eliminate cover fixings and the valve itself.


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