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Anyone using Shell V power on a tuned petrol engine?

6319 Views 49 Replies 10 Participants Last post by  Dave Kwatro
You may want to grab a brew or beer, then read this. :)

Shell, last month (April) 2021) revised it's blend of V power with Dynaflex giving more cleaning abilities and 4% more power.

Great, that sounds good! Right? Erm, maybe, I don't have any proof yet, but bare with me.

I have a tuned S5 3.0 V6 Supercharged. It was remapped 2 years ago on Shell V power. Tuners recommend using Tesco Momentum 99 when remapping as it gives the best results on reducing timing pulls due to it being souped up with Ethanol whereas VPower was other additives to increase the octane.

I believe VPower to be slightly superior over Momentum mainly due to its cleaning etc, where as Momentum is said to get you those extra few bhps on the dyno!?

Anyway, I'm not getting into 'that' debate shell Vs Tesco. This is different, I think.

I've been filling with Vpower for the past month or so, sometimes with the odd fill of Tesco. I didn't really see a difference in performance, maybe Tesco had a 'sharper' edge to it than Vpower. I also found mpg seemed slightly lower on Tesco.


Since last month, I have found my S5 to running sweet and seemed like it was pulling harder. Now I work from home, real everyday driving isn't comparable as driving the same route to and from work, so it may be placebo as I'm not driving as much, so just enjoying driving. But like I say it seemed to be driving very well like someone had tinkered with my ECU map.

I was having a blast when all of a sudden, the power went like it does when traction control kicks in, but I now always turn my traction control to sport (Half off) since the S5's power will spin all 4 wheels. So now when driving spiritedly, I do a quick cockpit check/change to exhaust flaps fully open, Traction to Sport, Auto start stop off, and Gearbox in sport manual. :)

Going back to the power loss. It started on the gear change into 3rd with WOT. Pressed the throttle a few times, nothing, then the power came back to normal. It did it once more on the drive and this was after driving for around an hour. No CEL lights or anything. Checking with VCDS gave P0089 Valve for fuel metering - implausible signal, P2279 Leak in air intake system - intermittent, P310B Fuel pressure outside Specification on low pressure side! Bowlocks!? I've read from the guys in the US that this is common on stage 2 and it's the tank fuel pump not keeping up with demand. Also going back to stock tune, the fuel pressure wasn't an issue as the demand is lower. But the Low pressure fuel pump should regulate at 5 bar, mine went to 7.3 bar!? so I would have thought a high pressure would be ok as it would still be supplying fuel? Anyway, according to the guys who have had this, the fuel pressure drops, then over pumps giving the 7.3 bar. The solution was to replace the tank fuel pump, but I'm not sure. My fuel system appears to be running fine and the fact the pump can do 7.3bar leads me to think it can supply enough fuel?

Still with me? In the US E85 (85% Ethanol) fuel can be used and it's equivalent octane rating is the same as race fuel, up at 105 (not sure if this is US rating). Also when running on with Ethanol the mpg goes down and a higher volume of fuel is used so the fuel pumps are working harder, hence the high pressure fuel pump upgrades like Autotech's HPFP piston upgrade.

Back to me. I went out again in the car and it pulled power again under WOT in 2nd gear. The fuel was V power and low level in the tank. It doesn't cut power every time. And no fault logs in VCDS since the first time it did this power cut.

I've been researching and pricing up the tank fuel pump as last resort to cure this problem. But last week, I refilled with Tesco and not filled with Tesco for the past 2 maybe 3 fills. Been on a decent drive, no power cuts, no fuel pressure codes in VCDS, but the power doesn't feel as sharp as the shell stuff now!?

Only time will tell and if I refill again with shell to see if the performance improves and if I get power cuts again!? I will obviously update.

But it's only with the guys in the US talking about needing to upgrade the fuel pump to flow more fuel which is what high ethanol fuels need, I looked at Shell's website and they revised their V power blend in April which is when I got this fault. The car has been as I said at stage 2 for 2 years with no problems!

Also September this year the UK government has announced ALL unleaded fuels are to contain 10% ethanol in the fuels (E10). It is E5 (5%0 at the moment. So will this aafect us with Ethanol demanding more volume? If this is true why doesn't the Tesco 99 give me fuel cuts it it's octane is upped by use of ethanol.

This is my car saga at the moment and not conclusive if it is the fuel blend or an actual issue with my car. But I do want to try Shell again as the 4% extra power, I think was there on my car!

I'm going for a little rolling road run to check my car's performance/health in a week or 2, so don't want another issue as before I had a charge cooler issue when mapping my car.

Fingers crossed it was a glitch. I'll continue with my 'testing' of Tesco Momentum and Shell.

If any of you can add to my findings or suspicions, please do let me know! :)
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That's interesting you got the power loss with WOT!? Do you turn traction off as this can feel the same when traction control kicks in and the flashing traction light is not always noticeable.

When was this? Did you mention it to Doug? Would you recall whether it was V Power or Momentum?

Strangely it did it twice after the first occurrences, when it logged the fault codes, but didn't log any codes since the first occurrence!?
That's the thing, it's not like I've just had a remap, it's been fine for 2 years, so it's either something to do with the fuel or my car :)

I was going to run on Momentum only for the rolling road sesh. But the fact it felt very peppy on this new blend of V Power, it made me think, but then again if it is the new blend giving the fuel cuts, then best to stick with tried and tested Momentum!?
Yep week on Sat! :)

Out of interest Joe and Mr Sayek, what fuel cleaner do you use?
On the other hand though Dave, would it be better to use the vpower and have your map tweaked to suit it? Might be worth asking Jason/Mike for their opinion as I'm sure if it's better they'll know.

Regarding fuel system cleaner I'm not too opinionated on a particular brand but I used Nitrox hot shot last time.
I'll give him a shout! and see. :)
I read some decent reviews on this cleaner
Red Line SI-1 Fuel System Cleaner

Not sure if any point using those basic Redex cleaner you see at petrol stations :)
Quite a few on the market.
I'm old school and think of Redex as more of an old fashioned additive for old 4 star engines. :) Although they do a few varieties now.

In theory, using V Power, I shouldn't need to use cleaners! :)
My Remapper has said they have seen good results from Esso Synergy Supreme 99! :)
But the nearest one to me is about 25 miles away!

As always, think the best thing is to buy and try and see which your car likes to drink! :) But as I said, as I don't do commuting anymore, this testing takes much longer! :D

But yes, I don't do supermarket fuels, except Tesco Momentum 99. Did you see the other week, Morrisons filled their tanks with sludge! About 30 cars were stranded around the filling station. The example drawn from the tanks at the station looked like an old tin of gloss paint where after 10 years it gets that browny sludge in it. :)
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Great stuff CREC guys! :) Good, well, not good, relieving to hear that other Stage 2 CRECs get this 'glitch'!
@Dippy - that's exactly what mine said, Actual LPFP was 7.3 and specified or default is 4.99 bar and the error log started at 1800rpm to 2800rpm, which was when I was prodding the accelerator in disbelief that my lovely S5 was having a wobble! :) AND this was 2 years and 8k miles after my remap! I periodically check with VCDS and never seen these faults before. I do get a sporadic PCV valve fault logged, but this is always at idle 700rpm and when the engine has warmed up!? I don't notice anything untoward. No CEL lights.

Not sure exactly how the 2 fuel systems work on the CREC engine, or how they switch between the 2 using the same tank fuel pump. I'm guessing the LPFP (tank pump) sends 5 bar of fuel to the HPFP, which has a line off before the HPFP piston/pump to the port injectors, then when demanded a solenoid commands the fuel from the HPFP to the direct injectors in the cylinders. Maybe at this point of switch over, is where we see this fuel pressure error? As it does seem to occur at or below 3krpm.

Dippy I've also contacted Turbo Zentrum in Trafford park for a FIS Controller! :D The more I think about it, the more I leaning towards getting one. Maybe a group buy!? If I hear noises of interest, I'll start a new thread on this. They won't be in stock until July.

So anyway, it looks like it isn't the fuel, maybe a glitch from the plethora of sensors and monitoring that modern engines have!? It could be an off batch of fuel?

@HTB - so your faults on the fuel pressure, were they just on the dyno and the 3 times fault, is this the same fault or something else to do with the ECU?

Be interesting to know if these fuel pressure logs appear on the previous gen engine as this only has the 1 fuel system, direct injection!?
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I would love to get the FIS-MMI but I was too tight-fisted to pay for the technology pack so I ended up with the Concert.

Sent from my IN2013 using Tapatalk
Yeah it is only possible with MMI 3G+ :(
Little update.

Went out last night, fuel light came on (sorry Simon :) ) so went and got some more V Power!

If it is placebo, it's a bloody good placebo, but the car feels better on V power (presuming it's the new blend!), tested the, as Jeremy Clarkson would say, POWEEER and it it does feel better than the Momentum! Also, not run a diagnostic check, but no power cuts, even at WOT and banging through each gear all the way to 5th! :)

Touching plenty of wood (British saying) the fuel issue seems to be ok!

I may have to go back on Momentum just to prove to myself that the new blend of V Power is now better than Momentum 99 as the weather does have an affect on the power or at least the way it feels. Not sure if the engine running nicely affects the gearbox changes, but they feel more like my Bro's M2, sharp and a little bit of kick, like the old SMG in the E46 M3 or a straight cut dog leg box.

When I plant the accelerator from a standing start, I heard the SC whine, not heard that before, especially on a CREC engine which has the SC clutch.

Not trying to say it magic fuel, but it does feel good on the placebo butt dyno!

1 point to add, I have serviced my airfilter as it's been 2 years, wasn't that dirty, but I've only done about 8k miles in 2 years and I made further mods to my air box. Totally removed the snow shield as I had just drilled holes in it and added another 25mm hole at the back on the box.

Anyhoo, to back me up please try some, you might like it. Bit expensive at nearly £1.45 per litre, but as I don't do the miles, I'm paying for the smiles.
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@Dave Kwatro

It's a cracking day for me to put the roof down and go on a 20 minute spin out for a tank full of Vpower. As you say, you don't own a car like this to worry about the cost of petrol, haha.

Sent from my IN2013 using Tapatalk
Yes it is and even better this weekend!!

I always keep thinking of a Cab, especially on nice days. :)

I think the way to tell if it's the new 'blend', it says Britain's best performance fuel on the trigger handle and some other Ads around the forecourt. My local one which is half a mile away from my house had big board stands further advertising it. But I guess all Shell stations will have it now.

Let us know! (y)
Ha ha! That's pretty much an open cone induction kit now! BUT, probably better as the filter is still shielded by 3/4 of the air box from the engine! Bet you can connect the secondary air induction pipe through the big hole, dead easy!?
Thanks Dippy!
Ah so by the mapping chart, it looks like the MPI port injectors work all the time and the fuelling isn't switched between the 2 systems. Interesting that the 3krpm has been a marker in some of these fuelling issues and also the end of 3xFSI.

Also, I have noticed the fuel cut about 3 times, but only flagged on VCDS once (I cleared the DTCs and it did it once more) and no CEL in any instance. But HTB had a record of the fault on the dyno, but no power drop. Maybe it's over sensitive!?
Yeah. No loss of power on each of the 3 occasions I've had the P0089; once on the road and twice on the Dyno

I'm basically ignoring it because it's only 3 occurrences in 5 years (or in 2 years since MRC stage 2) and it seems to have no impact on the car's performance.

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So you and Dippy have these faults logged but nothing noticeable in the performance of the car. I have noticed a power cut, but the power will be there again after coming off the throttle and getting back on it. Looks like some sort of glitch!?

Did you get the V power fuel?
I've got to tell you, its one of the best mods I've done to the car, it still looks totally stock from above, the cold side is totally open and doesn't seem to suffer from any heat soak from the engine, and I can hear the supercharger now but it's not ridiculously loud and I can still use the stock filter.
The best bit though... It didn't cost a penny.
Yeah that's what mine is like, can hear the SC, but I have only hole sawed mine and removed the snow shield. Mine cost £65 for the ITG cone filter. :) Makes £350 for some shields look a little over priced! :D

Have you replaced the intake pipe? I'm sure I saw that you had the IE intake?
@Smokey Joe Looking good Joe! I agree, open cone is a bit loud on the old whine. Mine probably sounds the same as yours, you can hear it, but it's not like an old A series gearbox (Mini/Metro).

Looking at your pic, I need to do my annual engine bay clean!! :)

@Redline_dtm1 Ade, I remember putting Redex in my plug holes on my Rover coupe Tomcat! It smoked like tyres on a fire! I thought I'd broke it! Eventually it disappeared! Best engine clean out and when the engine runs at it's best is after a trackday!! :D

Interesting what you say what Doug said, be interesting to know what that was, but then again HTB was tuned at MRC and he still had this fault code, so what ever it is, it doesn't affect this fuel pressure glitch. :)

I found on my 3.0TDi that the difference between std diesel and V power was V power pulled better top end but std fuel seemed to pull a little better low down!? :)
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I was low on fuel, again, light on. Floored it on the motorway and it went into limp mode with just the EPC light on. Engine was running smooth, just no boost. The supercharger wouldn't come in, no boost according to my FIS control, scrolled down in the FIS to fuel pressure and that was normal at 5.2bar low side and 128bar on the high side, intake temp was only 51 C as I had the charge coolant pump running full in this hot weather. :) Got my FIS control running properly the other week, but I don't drive much as working from home, but it is really good, especially when something happens like limp mode as you can check the stats instantly reading from the CAN-bus. Exhaust and cats were at 750 C. The EPC light hasn't come on before and the engine light has never been on.

Came off the motorway, turned off and on, all back to normal. :) Got some expensive V power fuel (£1.51 now!!!) Pulled like a plane or train, whichever is the best analogy for zooming towards the horizon. :)! Ran VCDS and no faults. Guessing the EPC light is more a plug or coil pack miss fire or possibly a gap in fuel supply as it only had 10 miles left, oops.

Even though the 3.0 SC V6 runs hot, or seems too, this hot weather doesn't seem to affect performance. :)
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So Dave, intake air temps. Have you seen any really high temps out on the road? What's your opinion on the charge cooler upgrade now?
Since fitting the FIS, I haven't been on a long drive so not got heat soak, well only after being parked. I've only done 30-45mins driving with some blasting on the motorway and it got to around 65 C. But when I've been parked up and come back to the car, it's been at 75-80 C! But as soon as I start the car and drive it does drop quickly to around 60-65C. On WOT it does initially drop by about 10C as the air rushes in and then starts to slowly climb as as it gets towards the redline. But the conclusion is, it's not hitting 80C as it did on the rolling road, but we did drive there, then wait a while, whilst it's strapped down. Then it's only run a little on the rolling road before going for it, so the heat soak won't have time to cool off. I reckon if the car was ran with some throttle to let the air in, but no heat producing boost for longer, then you might have a chance. But I think the pump will only run when on the throttle, maybe with boost, so unless you do the pump mod, it's not going to get chance to cool down.

From my limited drives, it seems to settle around 60C and drop initially when on WOT, but not seen the dirty 80C IATs, yet!

Got a universal heat exchanger on order, so will fit this and see what this does! For what it is and it does seem that we only experience limiting IATs on the rolling road, in the summer, I don't want to spend loads on a charge rad. The one I've ordered is the same as Merc racing was offering before they started to make specific rads for the 3.0T. I'm going with the stack route. I emailed a few places and it's basically £400+ for a big replacement rad. On Audizine, the stacked method appears to be just as good! The Jag XKR uprated rad, as far as I can tell is just a single pass. The uni rad I've ordered is a twin pass so the coolant has a longer trip/route on the cooling stage. For £145 for the rad, it's worth a punt! Most only went with a single large rad for aesthetics and a bit more cooling power. The combined surface area of the stacked route I'm going for is pretty much the same as the single large rad, so in theory it should provide the same cooling and stacked will also provide a 4 pass route.

I do want to try the rolling road again once it's fitted, just to see, but also want to wait until Autumn to get the best cooling for a map tweak. :)

Plus all fuels are going to E10 in September, so a remap maybe beneficial!? :) Might get more power as the guys do in the US using E85.
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Yeah, leaving the OE rad in, then putting the Uni rad on top. I'll gauge the position once I've got it, but there is only about 330mm from the top of the OE rad to the top where the slam panel cover is. So I'll see if the uni rad is the most exposed to air flow directly on top of the OE rad or better right at the top.

I'm going to get some 19mm aluminium piping (as you can get all sorts of sizes and bends etc on Ebay) and make the connections with straight hose as there will need to be a 180 degree bend out of the top of the OE rad into the bottom of the Uni rad, so don't want a hose to kink on that sharp 180 bend. Going to assess once I get the rad and what room is available. Might get some aluminium MIG wire to weld the pipes and mount points in the middle of the Uni rad as the mounts are top and bottom, so then I can bolt straight to the crash bar like the big single rads. But we'll see what the final fit is like after assessing and trial fits.

But researching the big rad kits, there is only so much cooling done upfront that the intercoolers in the supercharger then become the limiting factor! No point in spending thousands on a mahoosive charge rad when the small SC intercoolers still have a limit on how much heat they can soak out of the heated boost.
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Me too!

Ps, the rear caliper covers are nearing final stages! Just need to get the samples cut and trial fit them :D
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Hi Tony, could also be a dodgy connection.
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