Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle.  
Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - V69

Very loud knocking noise at idle speed. Camouflaged at higher revs but still detectible. Engine management warning light (car with spanner through it) on. No detectable deterioration in performance or fuel economy. My Vauxhall agent has the car in at present and has discounted vvt solenoid. Has now homed in on cam gears but cannot decide if one or both have failed. Suggests changing one, the cheapest I assume, but if this fails to solve problem the cam system will, presumably, have to be stripped again to change the other. From a cost point of view would it be better to change both together, plus timing belt, pulleys and tensioners. Mileage is 49,000 and belt has not been changed before. Advised 80,000 mile intervals by Vx agent. Urgent advice needed.

Tags: technical issues cam belts maintenance and servicing cam belt unexplained noises

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - Peter D

If the light is on then there will be error codes recored. What do they point to. The knock sensor could be triggering the light due to a timing error or a bearing problem. I doubt the cams would knock and a stethoscope with identify the area of concern. Have they inspected the cams for wear and check the clearance. Regards Peter

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - elekie&a/c doctor

These have variable valve timing gears and actuation solenoids on both the inlet and exhaust cams.Both the solenoids need to be removed from the cam box to see if there is are any metal /debris particles .The solenoids on these have a gauze oil filter strainers on them that are free to rotate and block the oil path to the cam variators.You will probably end up doing both vvt units and a belt kit,and make sure the oil is changed.(correct grade)

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - V69

Thanks very much for the advice. Spoke to garage this morning. The fault code indicates the exhaust cam is faulty but the inlet cam is also leaking oil. They were only going to change the faulty one but I told them to do both and, as you suggest, fit a new belt kit. The solenoids, apparently, are fine. I didn't think about an oil change but they won't start the work until Monday earliest as they haven't got the bits so still time to mention it. Thanks again. Will post how I get on next week.

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - V69

Just posting to say car is back with us having had all the work detailed in my last post carried out. Haven't had the bill yet. Expect they want me sitting down when I receive it! The result is a revelation. This is like a different car. NO RATTLE ON START UP, which was always there from when I acquired tthe car, engine smoother, quieter on the road and NO KNOCKING on tickover. Also, and this may be imagination but I think not, there seems to be better acceleration and more power. According to Vx Owners forum the rattle on start up is endemic with this particular engine and owners, myself included, complaining of this phenomenom, get fobbed off by most dealers with the "They all do it," mantra. My advice, based on this experience is don't accept this. Get something sorted out before things get critical and expensive as they did with me. Am currently wrangling with Vauxhall for some contribution but don't expect much joy.

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - elekie&a/c doctor

Yes ,"they all do it" ,but not for the right reason.The basic 1.8 16v ecotec motor is a pretty durable unit .They have only become unreliable since fitting this unnecessary v v t rubbish technology..Anyway,glad you got it sorted.Now for the battle of the bill.hth

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - V69

I'll report back!

Vauxhall Vectra C 1.8 vvt petrol 2007 - Pronounced knock on idle. - TeeCee

Sounds like the exact opposite of an MG Rover 1.8 "K" VVC unit. The hydraulic cam control systems on those are bulletproof and work very well[1], but the engine underneath is a well-known pig's ear.

I can't help thinking that there's a really good engine to be had by combining the best bits of both......

[1] Try driving something with one in. Quite astonishing. Not for the additional power, although it is there, but for the way it pulls like a train on steroids all the way through the rev range.

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