What petrol for a Leon cupra 1.8T?

[dano2387]

Hi everyone, i have only owned my leon cupra T for a week now, it was running perfect but then when i refilled up using a ASDA fuel station, it started to run lumpy and rough.... holding back and everything. I since refilled again but using normal fuel at a texaco garage, and its been fine....

Is this co insidance, or can fuel cause this? Thanks

 

[greesha]

Tesco 99 for me all the time .

 

[dano2387]

Thanks mate, also sholud i let my 1.8 turbo cool down... and if so for how long?

 

[revere]

You might find that if the car has been run on something like Shell Optimax or BP Ultimate only.

I've been told you shouldn't really run performance engines on much else especially if you have them remapped etc.

However, I cant afford to do that. I fill my car (Cupra R, 260BHP) up mostly at my local ASDA and I have never really noticed anything wrong with the car but I do know that the guy that had it before me didn't run the car on performance fuel. My mate who always ran his Mini Cooper S (240BHP modded version) on Optimax said that he put normal fuel in the car a few times and he really noticed a difference in performace.

 

[andycupra]

Firstly, if its been remapped then part of this remapping proceedure is to take advantage of good fuel and so you should use fuel that its remapped to.

The ecu is adaptive and this combined with the fuel is the issue.

Ill try to explain:
If a car does not have an adaptive ecu, then its settings will have to take into account variances in the quality of fuel and so will be a little 'safe' which clearly does not take advantage of the good fuel available. So in this case putting in higher performance fuel is not really worth it.

The 1.8T does adapt, its not something that happens instantly of within a fe seconds, but over a tank or two. So if you have been using decent fuel the ecu may adapt settings based on this.
It would appear that you have then used some fuel that is shall we say not quite up to standard of the fuel you usually use.
The 'settings' are then inapropriate for the fuel and so you saw poor running. Although usually the ecu would detect this and adapt fairly quickly. (it adapts quickly when reducing performance)

It appear that most people use super unleaded on this forum and many swear by getting a few more miles from it. As the ecu is adaptive this would make sense on this engine.

Some people will say that you MUST NOT use 95 ron on the 1.8T which isnt actually true, you can use 95 ron perfectly safely and with no issues; although it would be fair to say that the car will run at a slight in performance and this may well be pointed out in the manual. (you wont be able to feel the difference)



Regards cooling. Its not so much cooling the engine but that the turbo can get very hot when you use it. If you give the engine a hard time then park up this can lead to issues as the oil gets cooked as is no longer circulating.
Many people will say ' but the coolant continues to circulate after turn off for a while' - this is a bit of a red herring as its oil issues that the potential issue. (and im not 100% sure it does this on all 1.8Ts)

I would say that if you drive normally, then there is no need to cool down.
If you have been ragging it, then yes its a good idea to cool it down for 3 mins.
But why rag it then sit there for 3 mins, - its better to plan ahead, (~you know where you are going?) and rather than sit there on tickover foir 3 mins simply take the last few miles easy, better cooling and no need sit there like a lemon as the cars you have previously past park up and get where they are going before you.

 

[dano2387]

ok well like i said it was perfect, then used asda and it run like a bag of shi* changed my fuel and now its spot on again. ill keep a eye on it. thanks


Can i fit a dump valve to my car that will be loud, i.e non recirculating?? sorry if my question dont make sense- i dont understand dump valves. Just know i want one to be fairly loud. Lol

 

[revere]

ok well like i said it was perfect, then used asda and it run like a bag of shi* changed my fuel and now its spot on again. ill keep a eye on it. thanks


Can i fit a dump valve to my car that will be loud, i.e non recirculating?? sorry if my question dont make sense- i dont understand dump valves. Just know i want one to be fairly loud. Lol

It's a pretty well known that the LCR's dont really like the blow off valves, your far better fitting a re-circulating valve as you will get increased performance. I believe it reduces turbo lag between gear changes quite significantly !

 

[leon cupra r]

Chucked 15 quids worth of morrisons own brand in mine the other day just to see if it would manage to run on it, and I have to say I wasn't impressed... if its available I always get V-Power or failing this tesco99... unfortunately there arent either of these for about 15 miles of where I live so unless Im out that way, it usually gets 97ron superunleaded from somewhere like sainsburys...

Last 2 tanks have been V power, so went straight from this down to 95 ron, and definately noticed a difference in performance, just didnt seem to have as much kick to it in the higher revs.

The first few minutes it was running on the 95 you could tell the ECU was expecting 99RON and the engine didnt run as smoothly as it used to untill the timing was adjusted to suit, so for me it's pretty much confirmed that I am better off sticking to the expensive stuff as I have done to date.

I know it can work out quite a bit more expensive, but for the extra performance benefits, and also I do think there are economy benefits if you're taking it steady, I think its worth paying the extra.

People spend hundreds modifying to get an extra 5 or 10bhp, why not just spend an extra couple of quid when you fill up and enjoy an extra couple of bhp, its surely cheaper to do this than spend money tweaking and then chucking sh!te petrol in and not maximizing the potential of your hard work tuning!

 

[Muttley]

LCR's are specced for 98 RON fuel, will run on 95 but the knock sensors will retard timing and degrade performance and economy.

 

[8bit]

I was running low so went to fill up with V-Power and dammit! None available Tried the two Shell places near where I was but couldn't get any. Didn't want to stick normal stuff in but was too far away from another Shell or a Tesco so ended up half-filling the tank with BP Ultimate (97 ron).

Doesn't seem to be a huge amount of difference so far but maybe it takes as long for the ECU to adapt down the way as it does up, if that makes sense. I'll be going back to V-Power as soon as there's some back in stock tho.

 

[Scruff]

I'm pretty new to my LC so am still working out what i can expect from it. I personally didn't know they were mapped to run on 99 so after this tank of 95 that i put in the other day i'll go for the expensive stuff. Just to go off topic slightly, can anyone tell me what sort of mileage i can expect from a tank of fuel? So far i've done 60miles and the needle has hardly moved. Is it actually that economical or is my guage broken?!

 

[andycupra]

interesting they were mapped to a fuel (99ron) that wasnt even out when the car was made...

 

[rabe187]

i use 95 octane unleaded as thats the best available petrol Saudi

 

[dano2387]

I'm pretty new to my LC so am still working out what i can expect from it. I personally didn't know they were mapped to run on 99 so after this tank of 95 that i put in the other day i'll go for the expensive stuff. Just to go off topic slightly, can anyone tell me what sort of mileage i can expect from a tank of fuel? So far i've done 60miles and the needle has hardly moved. Is it actually that economical or is my guage broken?!

Its all down to how you drive it mate, theres 4.5 litres to a gallon as far as im awrare and if i drive it steady i get about 30 miles to a gallon, if i abuse it a bit, about 20-25 mpg. only estimates.

Dan

 

[dentist]

i once got desperate and put in morrisons unleaded ( No longer meets CE standards) and regretted it as it felt like my LCR had lost a cylinder lol.

only vpower/ tesco 99 for me!

 

[leon cupra r]

( No longer meets CE standards)

really? never knew that! will be avoiding even more from now on then!

 

[squirrelater]

interesting they were mapped to a fuel (99ron) that wasnt even out when the car was made...

Showing my age now, but when I was 17 back in '88 I used to fill my Ts100 motorbike with 2 start fuel, you could get 3 and 4 star, going back further, they used to say the original E-type jags had to run on 5 star, and that was 100Ron, Although I'm sure the Ron rating is fairly new, it was a bit less known and it was referenced as octain(spelling?)

Point I'm getting at is higher rated fuels have been around for as long time- good old 4 star was much better than the modern crappy unleaded.


To the OP's point, I've just switched to 99 ron Tesco and it is noticably better, waiting to see the range, although this tank is a write off due to <cough> being late a few times and buggering any change of getting decent mileage