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Search result for: 88 octane
| # | Post Title | Result Info | Date | User | Forum |
| Answer to: Rattle while accelerating | 20Relevance | 4 years ago | scottykilmer | Submit Your Question HERE | |
| Well the cat's taking his relatively normal but it sounds like it could be valve training rattle from worn timing chain or even gasoline that's too low octane. Any good mechanic can easily check the timing to see if the ignition timing is off and if it is that would have to be fixed. But a really good test is to put in a tank of shell super unleaded gas and if the rattling goes away then you know it's because the ignition timing is too far advanced and that higher octane gasoline will not rattle because it can take it better than low octane gas which will make the engine rattle | |||||
| Answer to: Ethanol free gas? | 20Relevance | 5 years ago | Justin Shepherd | Submit Your Question HERE | |
| Non-ethanol gasoline has a lower octane rating than E-10. It's really meant for law mowing equipment and farm stuff, ethanol can damage rubber in those engines if they're not designed to handle it. In a car, the rubber is more tolerant to the 10% ethanol by design, and it's added to raise the octane rating, which basically means the gas is less likely to prematurely ignite during the compression stroke. It serves much of the same purpose as tetra-ethyl-lead, popularly known as leaded gasoline. If you run E0 gas in your car, the PCM will detect the lower octane rating of raw gasoline and adjust timing to prevent premature ignition, which manifests as engine knocking. You'll lose performance and waste money, because straight gas is more expensive than E10, and having gas that is less tolerant of compression than the engine was designed for (regular E10) means the fuel won't burn as efficiently. | |||||
| Answer to: Shell gas | 20Relevance | 5 years ago | Doug Adams | Submit Your Question HERE | |
| the vehicle manufacturer recommends a minimum octane rating for your car. 87 octane probably is the minimum requirement. My car is supercharged so the manufacturer recommends 91 octane to prevent pinging in the motor, and possible engine damage. | |||||
| Answer to: Can i put premium or any other higher gas in my car ? | 20Relevance | 5 years ago | Kaizen | Submit Your Question HERE | |
| You can put the octane level recommended for your car or higher. The higher the octane, the higher the price for the gas. At the same time, it is wasted money since your car probably can't take advantage of the higher octane. | |||||
| Answer to: Do I need premium gas for an old Lexus | 20Relevance | 5 years ago | Mod_Man | Submit Your Question HERE | |
| If the manual says "Premium Required", you have to run it. If the manual says, "Premium Recommended", you can run lower octane but will lose MPG and performance. Long term use of low octane fuel in a motor designed for high octane will damage the motor. Do not buy a premium luxury sports car if gas expense is a concern....that would be the best advice. | |||||
| RE: Gas type | 20Relevance | 5 years ago | Kaizen | Submit Your Question HERE | |
| Same idea. Use the octane that is recommended for your car. Nothing less unless absolutely necessary. You can use higher octane on a car that requires lower octane with no adverse effects. But that’s just a waste of money. | |||||
| Answer to: What time of day to fill up gas | 20Relevance | 5 years ago | scotty_64 | Submit Your Question HERE | |
| here is australia we pay per litre and the price does fluctuate quite alot as there is fuel price discounting cycle. at the moment E10 is $1.30 aud per litre, then 91 octane is $1.36, 95 octane $170 and 98 octane $1.80. lpg prices are all over the shop, where i am i can pay between 66 cents a litre up to 86 cents per litre all with in a few kilometres away. when discounting of fuel prices are on in sydney, never buy after wednesday night as thursday it can jump as much as 30 cents per litre. | |||||
| Answer to: Supercharged Pontiac GT? & How necessary is premium fuel. | 20Relevance | 5 years ago | Dad2LM2 | Submit Your Question HERE | |
| I agree with Yaser to check the owners manual. But don’t be surprised if it specifies at least 91 octane. The point of forced induction (turbos and superchargers) is to increase the intake pressure within the cylinder. Then, with the compression stroke of the piston, you can generate even higher pressures at the time the spark plug fires. However, when you raise the pressure in a gas, you also raise the temperature. If the temperature rises high enough, you can ignite the fuel. (This is how Diesel engines run without spark plugs.) unfortunately, if the fuel ignites before the piston reaches the top of the compression stroke (preignition) you will have the rod and piston driven up by the crankshaft and down by the fuel combustion- at the same time. This is bad and can damage the engine. High octane fuel ignites at a higher temperature, and therefore prevents preignition. Modern engines can detect this and adjust the amount of fuel and air that go into the cylinder (reducing power and fuel economy), so that low octane fuel doesn’t damage the engine. But it isn’t optimal. And with that particular car, I would be very careful and follow the manufacturers instruction. Good luck, | |||||
| 97 pathfinder engine ping | 20Relevance | 5 years ago | ARS1218 | Submit Your Question HERE | |
| I’m experiencing some engine pinging anywhere between 1300rpm and 2500rpm. Especially good if uphill or when the engine is under more load with the A/C on. Everything has been maintained on it recently. New injectors, intake gaskets, IACV, TPS, MAF, Nissan plugs, new ngk leads, injector rail to intake seals, knock sensor, coolant hoses, new coolant. I did replace the distributor last year, again Nissan original part purchased. That I had my Nissan mechanic install. However he didn’t use a timing light. He just marked it up with the old one and then put the new one it. But I did really experience pinging much until now. I’m not sure if it’s the gas. I’ve been fulling for a while at a Mobil station with 87 octane. So I’m my last fill up I decided to 89 octane at a shell station. It was half tank I filled up on top of the previous gas. Still pinging so far. Should I wait a couple more fill ups with the 89? Try and octane booster? Or do I need the timing to be reset? | |||||
| 2001 BMW 325i Engine Runs Rough & Stalls - How to Proceed? | 20Relevance | 5 years ago | Yota | Submit Your Question HERE | |
| Hi Scotty! In July 2020 my friend purchased a 2001 BMW 325i (2.5L 6 cylinder RWD with automatic transmission) with 149,000 miles for $3000US from a dealer. The car looks and handles nicely but the engine is now running horribly. The cold engine, once started, only remains running for a second or two and then dies. He reports he must must greatly accelerate the car initially to get it moving. Once warmed up, the engine will die at stoplights if it idles for more than a minute or so. The car does not like to idle or travel slowly. He has no current mechanic and the car was not inspected by a mechanic before purchase. The car has an unknown service history. He has no OBDII diagnostic data at this point, nor are there any warning lights lit on the dash. He is not knowledgeable about cars. The engine air filter was inspected and found to be fine at the last oil change in October 2020. I should also add that he had been fueling the car with 87 octane gasoline when it required 93 octane from its purchase date until a few weeks ago. The problem has been only slightly better since Winter has passed in Wisconsin, and in the few weeks since since he switched to high octane fuel. He is considering going to the only local BMW specialist (looks reputable) he could find other than the dealer for diagnostics (likely $$$ labor rate) to evaluate the car and his options going forward (keep and fix or sell). Based on your experience, how do your recommend he proceed with this car? And, do you have any advice related to known problems on this specific car that he should know about. Thank you very much in advance for your highly appreciated response! | |||||
| RE: DIG vs Turbo | 20Relevance | 5 years ago | Razmig Bartassian | Submit Your Question HERE | |
| I wouldn't really say that octane and turbocharging are independent of each other, but I guess in terms of just concepts they are independent. All turbocharged/supercharged engines need to run higher octane gas because they have increased compression. However, modern engines like Mazda's new turbocharged engine can run a lower octane without risking engine knock but at the cost of some performance. Great write-up explaining all these though. | |||||
| RE: '06 Mazdaspeed 6 Power Loss, Sputtery feel in Acceleration | 20Relevance | 5 years ago | joshhuck | Submit Your Question HERE | |
| @Razmig Will do. Also, about the octane ratings again. All I understand about higher octane fuel is that it is less explosive which Im assuming is better for engines with higher compression ratios.. Is this why running a higher octane fuel recommended for a turbo? | |||||
| RE: Premium versus Regular in GS350 F sport 3.5 V6 306 HP 11.5 | 20Relevance | 5 years ago | Razmig Bartassian | Submit Your Question HERE | |
| Don't bother @mod_man some people just never learn things or even take some advice. We've experienced it before, and I actually hope they experience it as well so they know what we're talking about. They think a scientifically established octane rating for gasoline is a joke and obsolete for the function of an engine. Let's ask this question...why is there octane in the first place lol?! Why bother if they all run the same right?! There's been like 10 posts regarding octane...they don't understand. | |||||
| RE: '06 Mazdaspeed 6 Power Loss, Sputtery feel in Acceleration | 20Relevance | 5 years ago | joshhuck | Submit Your Question HERE | |
| @Razmig Alright so the oil is changed and with the tank about 40% full of 87 octane, I filled up the other 60% with 92 octane. I drove it around my area for about 20 minutes doing about 60mph. It cruises fine, and it felt fine on light acceleration but it still feels like its misfiring whenever I start getting into boost. I didn't go hard enough to throw a code this time, but im sure it would have if I did. I soon as I started feeling the shuttering I let off, and it was around the same RPM range, so. basically at the very beginning of boost I guess. I know we are still talking about the PCV system, and possibly the wastegate control arm/BPV, and maybe even a bad injector. Just wondering what to do next. If it is doing this just due to running 87 octane and non-API SN+ oil, is it possible that it could take a bit more driving before I start seeing results? | |||||