Hi all,

Just wanted to ask a question before calling in the cavalry,

On Wednesday morning went out for a family day, but as soon as I pulled away the car exhibited the following;

1) Loud knocking noise from the engine bay, can also be heard quite loudly outside the car,

2) Very poor and lumpy power delivery, even under the slighted load the car decelerates. Did not want to accelerate in 3rd or higher gears.

3) As soon as the engine temperature got to normal levels the problem disappeared.

Made it to a local garage where I checked all the fluids oil, water etc and all were found to be perfect. I was in the middle of the red on diesel so I filled up and we drove off again - this time with no problems.

Yesterday I drove up to Derby from Stevenage and there were no issues at all - however again this morning, started the car and it was worse than ever. Limped the car into work (again was ok when got to temperature) but now don't really fancy driving it until I know what it is and get it sorted.

I initially thought it sounded like big end chat as I've owned a few dogs over the years but to expect this on a 2011 plate with 26K miles?!

Any possibilities you guys (or gals) can suggest?

Cheers

Dean

Is this a mechanical knocking or do you think it sounds more like something rattling/touching under the bonnet?

If it was a mechanical knocking (engine internals) I wouldn't have even left the driveway, let alone nipped to to the local garage or driven to Stevenage!

On an 11 plate I assume it is under warranty? If so get on the phone to Skoda Assist ASAP - and don't tell them you've driven it as far as you have!

I'm assuming it's mechanical noise. It's a flat run from my house for the first couple of miles then it starts to get hilly, thats when I really noticed it so stopped, turned it off, left it a while then started it again. By that time I'm guessing the engine has picked up sufficient heat. Upon restart there were no noises at all and the car pulled perfectly.

Already spoke to Skoda Assist this morning and they mentioned it could be the oil pump? If that was at fault wouldn't it make that noise all the time? didn't mention the fact that I'd driven it the few miles into work.

But in any case it's certainly not moving under its own power until they get here to take a look at it.

Well Skoda assist came and had a look. Completely baffled the guy - said he'd never heard of this kind of problem before despite seeing 100's of CR engined motors across the VAG range.

Ran the full diagnostics on his laptop, no fault codes, started from cold - no knocking. Said it could be injectors giving mis-fuelling signals to the system but wouldn't know unless it was retested after a full day (ie fully cold system).

So I'm off to Wayside MK this afternoon to drop it off for the weekend and pick up whatever car they have waiting for me..

Edited 8 June, 201214 yr by Trilogy2k

I say fuel related, need to waste to minimal and refuel.

Edited 8 June, 201214 yr by alberg

Hi, Can't get the link as I need to be a member of that forum.

Can you copy/paste the interesting parts for me please?

Thanks

I say fuel related, need to waste to minimal and refuel.

Doubtful IMHO, as he refilled, so the only thing could be the crud in the tank.

I don't think that would cause knocking though.

Doubtful IMHO, as he refilled, so the only thing could be the crud in the tank.

I don't think that would cause knocking though.

He said that he retested with fuel, that could be from reserve or from almost full.

You would be suprised how diferent fuels have diferent behaviers on latest and older models.

I had a similar sounding noise on my astra diesel. It sounded like(how I would imagine)a big-end failure.  Turned out to be a fuel injector. When the faulty injector was unplugged, the noise went away, though obviously the engine was running on 3 cylinders (still sounded a lot better). I ended up getting the injector replaced. The knocking was really bad, I pulled into the nearest car park and switched off, for fear of the whole engine imploding.

Well to update the story so far;

Wayside Skoda MK called me yesterday and suggested to me that the fault was mine as they thought it was due to a misfuel. I started to doubt my own mind until I spoke to my fuel card company today and they confirmed all refuels upto the last one had been diesel.

I then spoke to the leasing company (I'm a company car driver) and they told me that they would have to take a fuel sample from the tank to determine if there is any contaminate... at a cost of £150. If its proven that the fuel is dodgy then I guess the blame would have to lie at the door of the petrol station I last fueled at? If not then they have to keep looking at other possibilities.. the guy did say that they get this quite often - the manufacturers are usually very quick at pointing the finger of blame at the driver when in actuality 9 out of 10 times it's another cause..

What damage could be made running diesel with too much water content?

Haha, I'd love to have been a fly on the wall in the service department...

"Nothing showing up on the diagnostics? Knocking? Sounds complicated. Tell the bloke it's fuel related, he'll soon get bored of trying to prove otherwise, chuck us another biscuit."