My 2.0 Roc had been misfiring and generally lacking in performance for over 6 months and I was getting a bit fed up with it. Changed the sparks, the coils and filters and even bought an ECU reader What I never thought about doing was changing fuel! I'd been suckered in by the lego offers when Shell began marketing the new Nitro + fuel and had been using it religiously. On Friday I filled up with some local 95 ron and so far, the misfiring seems to have gone! Whats even more surprising is the performance has returned. No more champagne cork at 2-4 RPM. Its only been over the week end but I'll report back on Friday hopefully with good news. Had a quick search on Google and it looks like this is not uncommon! Is this why Ferrari are doing so poorly this year?? Hope this helps someone else!
Strange, my experience is just the opposite. When I first got my 1.4 160 as a pre-owned, it had a noticeable misfire when at idle; on occasions so bad that I could feel the car rock! After a couple of months on Nitro the misfiring had noticeably reduced. I still sometimes detect what appears to be a slight misfire at idle, but the overall condition has without doubt markedly improved. Whatever cleaning agents they put in the fuel, workS for me.
I agree, its very odd...... I don't know enough about engines or fuel preparation to take the discussion any further so I guess if you find something that works, you've won a watch
My 2.0 Roc had been misfiring and generally lacking in performance for over 6 months and I was getting a bit fed up with it. Changed the sparks, the coils and filters and even bought an ECU reader What I never thought about doing was changing fuel! I'd been suckered in by the lego offers when Shell began marketing the new Nitro + fuel and had been using it religiously. On Friday I filled up with some local 95 ron and so far, the misfiring seems to have gone! Whats even more surprising is the performance has returned. No more champagne cork at 2-4 RPM. Its only been over the week end but I'll report back on Friday hopefully with good news. Had a quick search on Google and it looks like this is not uncommon! Is this why Ferrari are doing so poorly this year?? Hope this helps someone else!
Cheers
Paul
Might be worth using Redex Petrol fuel additive when you refuel, it's cheap and helps to clean the engine parts, hope this helps
Thanks mate, I might give that a try. Was never convinced fuel additives were worth it but will have a go. Just for info, the misfires are not 100% gone but they are much reduced and the performance is still much better than it was.
It could point to a faulty knock sensor. Certainly have it look at as misfiring is not good for the engine or the cat and can lead to more expensive problems. At least have it scanned.
Hi Cuprabob, I've had it checked by VW (Arnold Clark) who didnt "find" anything. They say they ran compression checks and swapped the coils around as well. I also bought a code reader and its not finding any codes either. I experimented a bit and ran some Tesco momentum fuel and the cold start misfire and generally ragged performance is back....... I'm going to run it with the bog standard fuel it seems to like again and see how it goes. I think I will pop it into a garage and see what they say though. I guess you cant program which fuel the car should run in the ECU? I mean can you tick a box for 97ron instead of 95ron?
Not exactly. The ECU advances the timing of the spark over a period of time until it detects "knocking" and then backs it off slightly. The higher the octane petrol, the more the ignition can be advanced. What's strange about your car is that it seems to be happier on lower octane fuel compared to higher octane, which tells me that something is happening when the timing is being advanced.
Whether a code is thrown up or not, something is wrong as the car should run happily on 95 or the higher grades of petrol.
What I never thought about doing was changing fuel! I'd been suckered in by the lego offers when Shell began marketing the new Nitro + fuel and had been using it religiously. On Friday I filled up with some local 95 ron and so far, the misfiring seems to have gone! Whats even more surprising is the performance has returned. No more champagne cork at 2-4 RPM. Its only been over the week end but I'll report back on Friday hopefully with good news. Had a quick search on Google and it looks like this is not uncommon! Is this why Ferrari are doing so poorly this year?? 