0
Low octane gasoline ignites at a lower temperature/compression than higher octane gasoline causing it to (depending on circumstances) ignite before the spark happens. This "preignition" or "detonation" causes excessively high cylinder pressure in the combustion chambers and at piston-to-connecting-rod near TDC and typically produces a knock noise which.
The preignition or "spark knock" can also damage pistons, valves, connecting rods, and bearings. Repairs may require rebuild of the engine.
Wiki User
∙ 16y ago
Add your answer:
Earn +20 pts
What type of gas should be used in a 2002 Volkswagen Passat?
At least 91 Octane. The higher octane is to prevent engine knock- esp susceptible b/c of the turbocharged engine.
Knocking noise when accelerating?
The knocking noise is commonly called spark knock. The knock can be called by the engine timing not being set correctly, or using gas that has too low of an octane for the engine.
Engine knock in a 2.2 Chrysler?
what is the compression ratio and recommended gas octane? try a higher octane fuel and see what happens, mileage may go up also.
What could be the reason for a small knocking sound in the engine of a 2002 Toyota Highlander?
I own an 02 Highlander, and sometimes I get a knock when engine is under load, like going up a hill or when accelerating. This is engine knock caused by low octane gas. When I use a mid grade or premium octane, I do not get the sound at all. .
Can regular gas go in a Nissan Murano?
The owners manual says that higher octane is preferred for best engine performance, but it also says that 87 octane can be used without damage to the engine. I've been using a mixure of 87 and 89 octane and do not hear any engine-knock or pinging. The gas mileage probably would be better if 91 octane was used, but I haven't run a test on that aspect yet.
Can you use 91 octane gas on a 93 octane gas car?
New cars with knock sensors to adjust ignition timing can run on lower-octane fuel, but you lose power.
Can higher octane gas reduce engine knock or reduce NOx emissions?
It will decrease engine knocking or pinging associated with detonation problems, and will posssibly burn more efficiently. It can, but if a higher octane fuel reduces or gets rid of engine knock and/or ping, I would recommend taking your vehicle to a mechanic for diagnosis. Moreso, if you have a Check Engine Light on even. It's possible that you have some carbon build up in your fuel system that is causing the knock and ping. As far as the Nitrous Oxide Emissions being reduced from higher octane fuel, I have no idea. But most owner's manuals outline which octane to use, and wouldn't recommend swaying from their recommendation.
Ford 4.6 Spark Knock Under load Where is the knock sensor located?
it depends on what engine you have but most of them are a 5.4 or 4.6 or 4.2 and those have the knock sensors under the intake manifold on the passenger side.
What is the difference between super unleaded gas unleaded plus and regular unleaded?
The difference is the octane rating, (in the USA)regular- 87 octane, plus is 89 octane and super is 91 or 93 octane depending on avail. Always use what the manufacturer recommends or higher Using a lower octane or sometime fuel from a no name gas station can cause engine Detonation/knock/pinging. This is when gas ignites by compression rather than the spark from the spark plug. Knock can(WILL) damage an engine if left unchecked, so it is not something you want to have happening. Though most new cars' ECM will adjust ignition timing if detonation is detected. The use of a higher octane fuel than required, can be a waste of money. Some newer vehicles can get better gas mileage with higher octane if the ECM will adapt to it/ depending on the vehicle(seen it mostly with pickups that haul loads). Using higher octane fuel "WILL NOT" damage the engine.
If 91 octain is required will using 89 or 87 octane damage the engine?
it can over time, octane ratings tell you how easly the gas ignites under pressure, the lower the rating the easier it ignites. higher preformence engines have higher compression and without the right gas the extra pressure can cause the gas to ignite early resulting in engine knock.
Can 98 mereceds c280 run on normal gas?
As long as it's not a diesel you can put any kind of gas in the car but if you don't use the recommended octane, then like any car you can develop engine knock and after enough time damage the engine.
Meaning of Octane Index?
The octane index is a means of measuring the gasoline quality of certain compounds. Therefore gasoline with a higher octane index has a higher quality and runs more smoothly. SO.........when you read 87, 89 and 91 for unleaded, superunleaded and premium at the gas station you are reading the octane index for that fuel. Essentially, low octane fuel causes for gas mixture to explode prematurely so the cylinders in the engine do not function properly and as a result, you begin to hear you engine knock.
