Dodgy Optimax?

Been using Tesco 99 for quite some time now and car supe running fine.

Couple of weeks ago i needed some fuel but had to get BP 97. Car Ok but not its self.

 

Last week had to get Optimax as was not near tescos, car has been a Bl**dy nightmare.

Drove it stanstead and back last week, it was hesitant, not boosting very well and generaly running like cr*p.

 

Gradually got worse until over last weekend it felt like it was only firing on 4 cylinders and at times it would not go above 10mph until i knocked it out drive and revved it to raise rpm and then get back into drive.

I reset ecu, no change

 

Managed to get to tescos this morning and fill it up with 99 again, its now driving fine again

 

Have Shell been watering down the Optimax or what.

...Have Shell been watering down the Optimax or what.

 

May I please note that it's not me posting under a 'ghost' account:eyebrows:

May I please note that it's not me posting under a 'ghost' account:eyebrows:

 

 

Lol at you John. Only have to mention Optimax and we all know you'll be in there somewhere!!

Gradually got worse until over last weekend it felt like it was only firing on 4 cylinders and at times it would not go above 10mph

i really dont think lower octane fuel would cause this, mine has run optimax for the last 3 (ish) years, last year i went touring the highlands of Scotland where they haven't even heard of Optimax so had to do 1000 miles on blogs brand normal unleaded crap, i never switched the boost controller on and never went above 0.6 bar and the car ran perfect, lower octane = det at high rpm/boost not practically stalling the car at idle speed, you sure you didn't put diesel in lol

I would have said check your plugs... but strange that it should be running ok now again.

How do people find tescos 99? I have a 25 mile round trip just to fill up with Optimax as I thought that is what everybody else used.

I only use Tesco99 since it was launced.

 

But seriously here, this loooks like a dodgy batch, which can happen in any garage, any brand.

Too much of a coincidence for me. Car has been running fine until i put the optimax in.

When the revs eventually picked up the first turbo started boosting at 2500 rpm, later than it usually does.

 

Plugs only done about 6000 miles, but i've got some hks iridiums to put in, but i dont think that will help.

Try filling with Optimax from another garage.

 

If those symptoms return, then you know it's the brand at fault.

If they don't, then it was the garage being careless (mixed with diesel, garbage, who knows...)

Remember Optimax degrades over time from a 'fresh' 98 RON to rumoured 95 RON!. This is why shell never put the RON rating of Optimax on their pumps to avoid false advertising claims

Remember Optimax degrades over time from a 'fresh' 98 RON to rumoured 95 RON!. This is why shell never put the RON rating of Optimax on their pumps to avoid false advertising claims

 

I'm not sure thats still the case to be honest. I know they didn't used to have the RON rating on there, and it used to be advertised as the same BS number as normal unleaded (BS EN 250?) as it was supposed to be just unleaded with additives. However, I know certainly the garage I use it says 97 RON and BS7800 on the pumps.

Remember Optimax degrades over time from a 'fresh' 98 RON to rumoured 95 RON!. This is why shell never put the RON rating of Optimax on their pumps to avoid false advertising claims

 

This should be on Snopes.com

 

-Ian

Could just be a bad batch. Like I said before they allow 10% of incorrect fuel in the barges before they empty them - could be the yokel delivery driver putting diesel in the Optimax barrel for the first 5 mins before realising!!!

oh, i aint had me supra that long, i been filling mine with just super unleaded and optimax occasionaly?? i dont have the turbo so will it realy make that much difference to me??

 

so is tesco 99 the best around then isit? is that what i should use??

I thought there was a test done with Tesco's 99 and it was 99 AT BEST, but mostly around 95?.................

I wish I could get 99RON

I run mine on Optimax (in the Highlands in Scotland Paul Mac) for the last three years and never had a problem until last week when I went to use the car after it (or rather I) had been off the road for a few months. Bugger to start, Wouldn't run smooth, wouldn't idle. Sitting with a full tank of Optimax which has gone off - gonna shove some octane booster in it this weekend

I had nasty black smoke after leaving it for a few weeks, put in 10 litres of new Tesco99 from a can and it cleared up within a few seconds.

Had fuel filter off last night to see if it was blocked but it was all clear, only done 2500 miles anyway.

Used supe this morning for work and running totally ok again, first turbo in at 2000 rpm and seeing 0.6 bar to about 1 bar boost when no. 2 comes online. Much more responsive from tickover as well.

 

I had this problem about 18 months ago, changed plugs, fuel filter, cleaned and checked all that i could but no change.

It was'nt until i started going from 95 to bp ultimate then on to optimax that it started to improve. I've been using tesco 99 for about 5 months now and car is running the best it ever has.

 

Could there be something else fitted that is not setup for fuel with octane lower than a certain figure?

 

My previous supe, which was virtually indentical, ran quite happily on 95 with none of the probs i've had recently.

I run mine on Optimax (in the Highlands in Scotland Paul Mac)

lol TBH mate i went in a little service garage and the rather gruff old man looked blankly at me and told me in no uncertain terms they didn't do Optimax so i filled up with normal and never bothered looking again, like i say though the car ran fine on normal (93 is it ?) for 1000 miles