Always used Optimax and O/B on both the STi's ive had, and the knocklink has always ben pretty quiet.

I was running low yesterday and filled up with Ultimate and poured the usual of OB in there. This morning I was giving it some beans and the red light popped up to say hello Tried it a couple of times and got either top orange or red at 4-5k rpm.

I know others have seen this too, and ive always just thought it was people jumping on the band wagon.

Despite the fact I should use it I'll stick with Shell.

At least it tested the KL out

MB (STi5)

 

I had to fill up with ultimate on Sunday in my MY00, and i was getting so much 'knock' detected by the ECU that it was running in 'safe' mode.

I have now managed to get rid of all the fuel in my tank, and I have a tank of Optimax in again, and all is happy with my car now.

 

I sent BP a mail via there website contact form, and I have had a response asking for more details, and they are going to investigate everything for me.

 

thanks for the info guys. I've not got any mods that would seem to warrant a knocklink yet, but having read IanW's contribution I'm wondering whether its a good idea to get one on a standard car to check for dodgy petrol. I always use optimax, but one of these days might get caught out!

Best.

 

My car doesn't have a huge ammount of mods, PPP, STi intercooler, and a full de-cat, however I do have gauges monitoring things, i would much rather know of a problem before it is too late.

 

If using non optimax I would go for esso super unleaded next. You wouldn't catch me putting BP ultimate in. I have not heard anything but complaints as to cars not just detting, but running very roughly.

Worth having a knocklink on a completely standard car. There are always chances of dodgy fuel or other fuel supply related issues which can be flagged by a sparkly knocklink.

 

Yup I agree with Adam. I didn't have much choice but to fill up from BP, as i didn't have enough fuel to make it to the nearest Shell garage that I knew of which was 50 miles down the M6 (or there abouts).

I would much rather pay £140ish for something to monitor, than have to pay a couple of thousand pounds for a rebuild.

 

Seems i may be a lucky one. Usually use Shell but now and again i've had to put Ultimate in. So decide to watch the knock level on the Apexi PFC, could really notice any change. Certainly no noticeable spikes.

Will still stick to shell tho.

Tony.

 

Pre Link and GEMS my 99 UK detted its **** off on Ultimate.

God awful shyte IMHO

 

Agree with Adam - Optimax 1st choice and Esso SUL 2nd
On a rare occassion had to fill with Ultimate whilst out and noticed increased Knocklink activity so turned boost down to be safe.

Cheers

 

nearest garage is BP so utimate has been the fuel of choice since bought the car a few weeks back. I have always taken the few flashing lights for granted under heavy work, cos it never got high enought o cause concern but now you come to mention it, the knock link has been flashing at all this week since optimax went in.


mmmm, i will do my self a bit of an experiment tomorrow.

 

The problem will lie when switching from Optimax to a poorer grade, as the active knock correction from the ECU will be expecting good fuel. If you use Ultimate for a long period, I suspect the ECu would compensate for it after a while. If you then switched to a higher grade, the ECu would adjust for this and you might get a bit better performance. If its an STi import then the ECU may not have enough margin to compensate for poor fuel and thats where you run into det probs.

Interestingly, on the rare occasion I use optimax alone (without booster) there's only slightly more KL activity. But using the ultimate and OBthe other day, it was quite severe....

MB

 

Had to put Ultimate in just before the Jap Show at Santa Pod last Sunday, didn't really notice any more Knocklink activity (not that i get much anyway) but could not get any decent runs up the strip that day and only just improved my times (when it was standard) even thought i now have a decat & remap (well that's my excuse and I'm sticking to it ).

 

Mark,
Seeing as yopu work where you do!!!! maybe you should start some investigation from the inside!!!

 

Best not to rock the boat Ron, I imagine it would be a touchy subject

MB

 

i had to fill up on the m1 a few days ago with ultimate @ 95.9p/litre

i stuck 50ml of Nf in as well to stop it detting

 

Surely it's all down to the flame front burn thingy masking the det with optimax mycroft used to go on about?

 

LOL

mycroft invented ultimate didnt he?

seriously tho, i was driving back home from reading and i overtook a soarer today and i actualy did think about "mycroft" which is ****en wierd cos i dont even know what he looks like
but i imagined him to be like his "heres johnny" avatar he uses on other forums

i had heavy clubbing weekend mind lol

 

I do the same when I go past a Soarer They all look like they could be him

MB

 

he is about 6 ft 6 if that helps!

with regard to problems with ultimate, bear in mind that the knocklink will be more affected the closer your timing id to the limit.

If your car has an aftermarket ecu and has been mapped to be VERY safe, then you might find no difference in knock activity once switching to nasty fuel.

If however you are on the limit, ultimate might be just what was needed to push you over the edge.

The safety margin in the map will mask any problem with the fuel, except for rough running which is also a symptom.

 

I have previously documented my problems on Ulti-pish so wont bore you with the details.

re: mycroft, wasnt it a green soarer in the Oxford/Newbury area?

 

if your talking about me then i did see a green soarer around them areas

i think i was on the m4?