New turbo on vrs, low mpg?

[sc0rpius]

Hello, the turbo on my octavia vrs (02) plate blew recently because the oil pump was clogged up and oil wasnt reaching the top of the engine, so after a new oil pump and reconditioning the turbo i finally got it back on the road.

I put £20 worth of Petrol from Shell in on Saturday, so ive only done 73 miles and the petrol lights on (it came on around 60-65) the gauge is at the bottom and the miles left gauge says either 5 or 0.

What could be causing this, ive also noticed that its a bit slower then before apart from that theres no warning lights on the dash and it drives normally, no smoking either.

Could it be the oil needs changing again, they've done it once after the oil pump was changed and then again after the turbo was put back in. Or is it a sensor or something?

[SideshowBob]

You say that oil wasn't reaching the top of the engine.... was the head checked over once the oil pump issue was found? Leakdown test done?

[KenONeill]

As Bob says, if oil wasn't getting up the top end (as distinct to just not reaching the turbo) you could have jammed hydraulic tappets, worn camshaft bearings and/or lobes.

[sc0rpius]

As far as I know they checked everything and they cleaned the oil that was stuck in some places (the names of which i cant remember now..).

[sc0rpius]

i just phoned my cousin hes got a 04 vrs with a falulty air flow meter and he says he's getting around 100 miles to £20.

So could it just be the octavia vrs is just a heavy guzzler?

[chicken_eyebrow]

Might be worth checking the turbo has been attached to the manifold and downpipe securely, if there is a large leak then the exhaust gasses will be leaving the engine pretty much unrestricted which is for performance but for fuel economy!

As a guide my VRS does 360 miles to a £55 tank of super unleaded

So for £20 you should be able to get about 130 miles as long as you're not ragging it

Edited 23 February, 2010 by chicken_eyebrow

[sc0rpius]

I use normal unleaded aint it just cheaper to use that instead of super. What benefits do u actually get with super.

[Beretta]

I use normal unleaded aint it just cheaper to use that instead of super. What benefits do u actually get with super.

All Octy vRS's are designed to run on 98 octane fuel or above, they do not perform as well on 95 octane.

I always ran mine on Tesco 99 octane.

It should marked inside your flap for the filler cap?

[sc0rpius]

Ive bought some injector cleaner shall i put it in before or after i put in petrol. All it says is add to full tank.

[chicken_eyebrow]

Usually just pour the whole bottle into an (almost) empty tank then fill up the rest with petrol.

And super is deinately worth it. If you have put normal 95 ron unleaded in your car for months then you put 98 ron in you will notice it goes much better! Also you get about 20 more miles out of a tank of super which more than covers the difference in price between super and normal.

[sc0rpius]

Rite ill do that tonight. Is it orite if i just put in 20 pounds worth after putting the whole bottle in?

[SideshowBob]

Sc0rp... You will need to run a couple of tankfuls of 98/99 through it before the ECU adjusts properly to the higher grade fuel. Once you're used to it if you have to put 95 in for whatever reason you will definitely notice it has taken the edge off the performance, and less MPG too.

[sc0rpius]

Cool, that sounds good. I will probably get it converted to LPG in a few weeks time, get a nice big 90-100L tank in there.

[karlbar2k]

if you go for a toroidal tank in the spare wheel well the biggest you can hope to fit is about 65-70L if you get the non-donut type, mine is 60L so takes about 51-52L to fill and I get about 230-270miles to a tank depending on how much effect gravity has on my foot One thing to be aware of when you go LPG with tank in the boot is the weight distribution is slightly different as the tank will be a bit higher and further back.

[ExAudiSi]

To work out your mpg accurately, you need to brim fill the tank and then run the car until you need fuel. Fill it up gain and see how much fuel you need to add and how many miles you have done since the previous fill.

The fuel gauges / lights aren't that accurate so saying you don't get many miles on £20 could just depend on when the light comes on.

[KenONeill]

Rite ill do that tonight. Is it orite if i just put in 20 pounds worth after putting the whole bottle in?

I'd run the tank as low as I dared, add the cleaner, then fill right up; the idea is make sure the cleaner is evenly mixed through the fuel. I mean, you've a bit more muscle than me if you can pick the car up and shake it!

[sc0rpius]

Rite tank needle was at the lowest point i then put the cleaner in and 55 pounds of shell v power which must have been more or less full as it stopped at about 54 then i had to fill it up stopped myself as thats all i had. Just topped my water up aswell.

[sc0rpius]

Well it got 195 miles then the petrol lite came on but it said 25 mile range left. Not very good plus it definately is slower then it should be even my cousin said whos got a vrs too. Ive driven his and it feels quite a bit faster. So wot could be the problem? Could it be some blocked pipes full of oil or something?

[chicken_eyebrow]

Ouch that is using fuel quick.

Any signs of fuel leaking from anywhere? Any leaks from the pipes from the tank to the fuel filter, or fuel filter to the fuel pressure regulator and fuel rail?

Has it been fault code scanned? May be running rich for any number of reasons, a fault code scan may pick some of them up.

Also as before has the turbo been fitted properly, if it is not secure on the manifold then not only will the engine drink fuel (because the exhaust gases get out a lot easier) but also the turbo won't spool up properly which could be why it feels slow

Edited 2 March, 2010 by chicken_eyebrow

[Ecomatt]

If I was you. I would get my car scanned for any fault codes? Failing that I would take my car to a tuner who can log the data via vag com etc, to see what the engine is doing under load. Plus have a visual inspection around the turbo, manifold etc for leaks. Was the turbo a new or recon unit?

[sc0rpius]

He reconned the blown turbo. Wots the easiest way to visually check if the turbos on properly bare in mind im no good with cars.

Edited 2 March, 2010 by sc0rpius

[chicken_eyebrow]

With the car stone cold, look behind the engine (you may have to move covers/hoses/heatshields out of the way) and find where the turbo connects between the manifold (the set of pipes coming off of the back of the engine) and the exhaust. It should be bolted on, have a fiddle with the bolts with your fingers and see if any feel loose. If you can get under the car (eg. in an inspection pit) you can see where the turbo connects to the downpipe, again check if any bolts are loose there.

Then start the car and while someone revs it, look for any exhaust fumes leaking from around the turbo area.

Edited 2 March, 2010 by chicken_eyebrow

[sc0rpius]

Thanks for that info, well they've connected a fault code machine to it and nothing shows up as any faults my cousins whose a mechanic and his own vrs says that because the oil wasn't reaching the top of the engine that the engine has been permanently damaged and lost the compression and thus loss power basically saying i cant fix it. Could he be right?

I'll try that turbo thing, if not ill call someone to check the positioning.

Incidentally if you floor your car in first for those with standard vrs's (180 bhp) at what revs do u reach 40 mph?

I think the turbo is working properly because I can hear it and feel it kicking in but the cars shift/boost does not feel as smooth or fast as my cousins vrs whose engine has done about 30,000 more miles then mine! Mine is at 73k, FSH. 2 owners.

[chicken_eyebrow]

Garage should be able to do a compression test on the cylinders to tell if there is more serious damage. This could be headgasket failure, worn or damaged pistons and piston rings, a cracked cylinder head, worn camshaft or damaged valves. Either way it's not going to be a cheap fix. If the turbo is working ok then you might have to start looking for a cheap 2nd hand engine to have fitted or at the least a new cylinder head.

Edited 3 March, 2010 by chicken_eyebrow

[sc0rpius]

Well i opened the bonnet and my m8 revved it the fumes were all coming from the exhaust didnt see anything coming from anywhere around the engine next step compression test.