Hi all,

For those that have paid to have the carbon build up removed from their inlet valves, how much did it cost and more importantly did it cure the cold rough running symptoms completely?

Going to get a quote from my local indy and want to know whether I should be sitting down or not when he quotes me!

Have a look at Terraclean. About £90 for a treatment and it looks to work on direct engines too.

Have looked at that system before but couldn't convince myself that it would work.

Doesn't the problem arise from lack of fuel wash over the valves? I believe Terraclean is delivered via the fuelline.

Anyone tried it and had a result?

Yeah it doesn't wash over the valves in a DI engine its a head off job and depending on how bad it is the valves may need to come out too..you're gonna need a new head gasket, cam cover gasket, head bolts, timing belt kit, new engine mount bolts, inlet manifold gasket, exhaust manifold gasket and a coolant change.

Edited 14 May, 201313 yr by 07 vRS Taxi

I've got an invoice somewhere, but off the top of my head it was £2200.

That included cambelt and water pump though.......

You could try seafoam, heres a DIY of someone doing it on their golf

Ive tried seafoam and I didn't get as much smoke as anybody on YouTube, this is as good as it gets and only lasted 10 seconds ish. It was quite dangerous though at one point it was back firing up the tube out of the funnel and into my face.

Sent from my LT26i using Tapatalk 2

Edited 15 May, 201313 yr by 07 vRS Taxi

£2200 - think I'll need a lie down not a sit down if he quotes anywhere in that region!

How do you know if your car needs this,or is that a dead cert?

It's been in various times to be looked at. It's not the temp sensor or the coils. It has no fault codes logged. Real time diagnosis whilst driving shows nothing untoward or outside of parameters. The symptoms fit that of carbon build up from what I understand.

Tempted to try seafoam or similar as a cheap fix. I suspect it will prove there is no such thing as a cheap fix, but currently hopeful!

£2200 - think I'll need a lie down not a sit down if he quotes anywhere in that region!

How do you know if your car needs this,or is that a dead cert?

Mine was quite bad. Valves couldn't operate they were so coked up, causing persistent misfire. Head had to be sent away to be machined, valves all cleaned etc.

Basic engineering. suck, squeeze, bang, blow. Suck - induction - where the engine draws in clean air into the cylinders via the inlet valve. If the inlet valve is sealing there will be no carbon build up. Squeeze - compression - both valves closed and towards end of stroke is where fuel is injected in to cylinder (either petrol or diesel). Redirect/indirect diesel with indirect it is still into cylinder via a pre combustion chamber. Still not lubricating inlet valve. Bang - power - both valves still closed, this is the big bang. Still nothing going into inlet valve if sealed and exhaust valve then starts to open. Blow - exhaust stroke - piston on way back up. Exhaust valve fully open. exhaust gasses on way out to turbo or exhaust

If you put a good quality cleaner into your fuel it should clean the exhaust valves. Old trick was to take air cleaner out and squirt some cleaner into the inlet tract

Mine is run on decent fuel and whilst my indy was scratching his head over what the problem was he put a Wurth system cleaning product of some description in the tank gratis to see if that would help. It didn't.

I suspect that he was hoping it was muck somewhere it shouldn't be.

Basic engineering. suck, squeeze, bang, blow. Suck - induction - where the engine draws in clean air into the cylinders via the inlet valve. If the inlet valve is sealing there will be no carbon build up. Squeeze - compression - both valves closed and towards end of stroke is where fuel is injected in to cylinder (either petrol or diesel). Redirect/indirect diesel with indirect it is still into cylinder via a pre combustion chamber. Still not lubricating inlet valve. Bang - power - both valves still closed, this is the big bang. Still nothing going into inlet valve if sealed and exhaust valve then starts to open. Blow - exhaust stroke - piston on way back up. Exhaust valve fully open. exhaust gasses on way out to turbo or exhaust

If you put a good quality cleaner into your fuel it should clean the exhaust valves. Old trick was to take air cleaner out and squirt some cleaner into the inlet tract

It's on valve overlap when the exhaust gas breifly escapes into the intake, near the end of the exhaust stroke the inlet valve starts to open ready for the descent on the intake stroke. If you turn the engine off and it stops in this position it does a lot more damage. Newer DI engines don't suffer this as they had to cut out valve overlap.

I thought it was also a by product of how the EGR valve operates. Hence how Terraclean works on DI engines.

That also comes into it but more so valve overlap as newer DI engines don't suffer a coked up intake and they also have an EGR.

That does come into it but more so valve overlap as new DI engines also have an EGR but don't suffer a coked up intake.

It is quite a complex issue as the PCV gases also come into play.

Basic design flaw with DI engines - there isn't anything washing the inlet valves, so there is nothing to clean up after the valve overlap, EGR and PCV gases and they get cooked onto the inlet valves and ports.

Some talk of the newer VAG DI engines having a fifth injector to get round the issue.

Morning all,

I have spoken to my nearest Terraclean garage. He offers no guarantee that it will improve matters. He says that it "should" help as it would get to the coked areas due to the valve overlap.

He claims to have had sucess with an Audi with similar symptoms.

Worth a punt at 100 notes or are we in snake oil territory with this?

Suggestions welcomed!

Nosing round the net this morning, the Audi boys seem to be having some results from Wynn's DIP3. Anybody tried that one?

I would save my money. The only person with nothing to lose here is Terraclean garage.

Morning all,

I have spoken to my nearest Terraclean garage. He offers no guarantee that it will improve matters. He says that it "should" help as it would get to the coked areas due to the valve overlap.

He claims to have had sucess with an Audi with similar symptoms.

Worth a punt at 100 notes or are we in snake oil territory with this?

Suggestions welcomed!

That depends on how efficient Terraclean is when it has been reduced to exhaust gas? Ask them as that's the only time it will briefly get into the intake.

Nosing round the net this morning, the Audi boys seem to be having some results from Wynn's DIP3. Anybody tried that one?

Same idea as my above post on Seafoam...

That depends on how efficient Terraclean is when it has been reduced to exhaust gas? Ask them as that's the only time it will briefly get into the intake.

My thoughts exactly!

Edited 25 May, 201313 yr by steve33

Doesn't the terraclean only clean up the fuel entering combustion chamber?

There are other products that will clean inlet ports where the carbon build needs cleaning from