CatmanV2
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I knew someone would pull me up on the SUL recommendation and you were safe bet
I'd hate to have disappointed you
C
Rev problems with 4200 CC
- Thread starter richi
- Start date
I'd hate to have disappointed you
C
Wack61
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I'll bite, when I had my Impreza mostly I ran it on 99 ron Tesco momentum, the odd few times I ran it on 95 it didn't tick over as smooth and definitely had less power , whether the turbo engine prefers the higher octane fuel compared to NA I don't know but when I get a Maserati I'll be running it on momentum
Given the low use of most of the cars on this forum compared to the garage bills £5 a tankful on premium fuel is worth it just in case it's doing something magic in the engine.
CatmanV2
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I have a magic wand, better give me £5 in case it works
Seriously, turbo engines could well be better suited to higher octane fuels so I'm not going to gainsay that in the Scooby. Also, on my old Ducati Monster, 99 octane *did* help stop the carb from icing.
C
I had something similar on my 2002 cc Spyder that I only found out after I bought her as I did not rev that high during the test drive. I would suggest one possibility might be the HT side breaking down/earthing. After quite a bit of investigation, turned out that something had chewed through the underside of one of a couple of the HT leads.
The car ran absolutely fine until hitting 5000rpm and then it was like hitting the rev limiter. There were no error codes showing with lower revs, but once above the 5000 range, then as the independent put it "it all lit up on the error code reader". Thankfully quite simple fix, but lengthy investigation and all covered by the dealer warranty (after some heated discussions).
A few lessons learnt for me - always get and independent inspection, plus decent warranty - and drive the car on the test drive as you would want to once the car is yours.
good luck.
David.
The car ran absolutely fine until hitting 5000rpm and then it was like hitting the rev limiter. There were no error codes showing with lower revs, but once above the 5000 range, then as the independent put it "it all lit up on the error code reader". Thankfully quite simple fix, but lengthy investigation and all covered by the dealer warranty (after some heated discussions).
A few lessons learnt for me - always get and independent inspection, plus decent warranty - and drive the car on the test drive as you would want to once the car is yours.
good luck.
David.
Zep
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Zep
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The thing with the octane rating is that its all about knock resistance, it is a measured on a test engine with a variable compression ratio and its performance compared with iso-octane.
Turbocharged engines benefit more because they have higher cylinder pressures and so therefore are more prone to pre-ignition, higher octane allows more ignition advance and higher boost pressures before the knock sensors retard the timing. The benefits on a N/A engine are much more subjective as the dynamic compression is generally much lower. Or something...
Hi David, thanks for you information, much appreciated! That really sounds like a similar problem to me! As you pointed out, the car works without any issues until that point. Just to make sure that I got it right: you're talking about spark plug wires attached to the sparks, right? If the other stuff (gasoline, etc.) doesn't work out I will have to bring it to the independent eventually and will let him know where to look first!
Hey Guys, I am still struggling with that issue but I can provide some latest developments that may be interesting. Following your advice I took the car out and refueled it with Shell V-Power 100. I thought that it was running smoother but that might as well be imagination. The problem however, still occured on several occasions (i can't rev it that high when i'm in zurich) but I noticed that it does NOT stop at 5000rpm. It was higher once or twice. Also i think that the failure starts to show in other situations such as if it had no air and "almost shuts off" for a second, less power also when warm, etc. But then a yellow (i read a lot about this light being red but mine is yellow?) light appeared and i thought there was an issue with the F1 pump again since I thought this light was on when it didn't start anymore because the gear was stuck due to pump failure. Already contacted the indy about bleeding the CC oil again etc. But now I looked it up in the manual and it says that this is an EOBD fault.. I know that a reader would be very helpful and I already ordered one but it didn't arrive yet! You think this could still be connected to the pump issue or is this an entirely new problem connected with the power loss and revving, jittering, etc.? Hoping to get it sorted out asap since i would like to focus on more enjoyable matters such as back boxes!
hladun
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Richi,
You're a classic example of how not to troubleshoot a problem. "Order and method" as Hercule Poirot said. Some suggestions:
1. You HAVE TO READ THE CODES.
2. Don't post that a light went yellow...what was it, the traffic light?? If you give poor information you get poor answers (guesses on our part).
3. If you post useless chat then the people that can actually help you stop looking. Their cars work and they're busy driving them.
You're a classic example of how not to troubleshoot a problem. "Order and method" as Hercule Poirot said. Some suggestions:
1. You HAVE TO READ THE CODES.
2. Don't post that a light went yellow...what was it, the traffic light?? If you give poor information you get poor answers (guesses on our part).
3. If you post useless chat then the people that can actually help you stop looking. Their cars work and they're busy driving them.
Hi contigo, just did what you suggested and let the sensor outside hanging.. went for a short test drive and it absolutely seems like switched out!!!! genius! it runs very smooth and has a lot more power with higher revs but imust say i didnt go too high because it wasnt warm yet.. i think it had less power with low revs but runs very smooth instead.. no jittering at all. does this mean that that the maf is defective or it has to be cleaned? Or is it the air filter and it runs better because it can susck the air in from that small opening of the sensor? Thanks again!
it runs very smooth and has a lot more power with higher revs but imust say i didnt go too high because it wasnt warm yet.. i think it had less power with low revs but runs very smooth instead.. no jittering at all. does this mean that that the maf is defective or it has to be cleaned? Or is it the air filter and it runs better because it can susck the air in from that small opening of the sensor? Thanks again!
GeoffCapes
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I thought Benny got the blame for everything. Are we now blaming Mark?
Contigo
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Hi contigo, just did what you suggested and let the sensor outside hanging.. went for a short test drive and it absolutely seems like switched out!!!! genius!
Cleaning may help, use a proper electrical or MAF cleaner if you can get one. If I remember correctly with the MAF disconnected it will use the TPS and AFM for readings instead (some us speed density) and by unplugging the MAF you are eliminating it from the loop. The fact that your car now runs smoother and revs higher with the MAF out of the equation would naturally point to it being faulty.
Get the code reader, read the codes and see if that too confirms things.
Hi Phil, I just picked up the car from the indy yesterday. I had him replace the whole MAF Unit with the housing just to be sure. Before that I had him read the codes.. first he said that he already tried and it didnt let you read it but then we managed to chose another car (some Alfa 4.7L) and it came back with two errors: MAF and another one that was linked to it. After replacement the car runs normally. The only thing I noticed was that when the engine is cold, it runs smoother with the MAF disconnected when clutching in. I will replace the sparks (the denso ones recommended here) and maybe the air filter after that..
So thanks again to all of you!!
So thanks again to all of you!!
Raulpereg
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Hi all. I think I have similar issue. It seems in 2nd and 3rd the car sometimes struggle to go over 5,5 rpm, it goes but as it does not have more power. Please, could anyone explain what is the MAF and how to disconnect to check? Im also having overheating problems when going to high revs, so no sure if can be also part of the problem.