What oil do you use in the engine when low - 2003 Yamaha V Star 1100 Classic

Very likely tell you that you have low engine oil level. I surprised that you didnt kill engine driving like that. If oil level is ok then it may indicate low engine oil pressure. See mechanic.

Do you mean what causes low oil pressure? This is a very reliable engine for the most part. If the oil light is on or gauge is reading low, have the oil pressure sensor inspected for failure. These sensors do go bad.

1. Engine Noise. With a bad oil pump sufficient engine oil will not get to all parts of the engine, especially the top end, and you will get engine noise with metal parts that would normally be lubricated and quiet knocking due to metal to metal contact. Engines with hydraulic lifters that become noisy can be a sign that they have insufficient oil supply. In addition to the hydraulic lifters, your valve train may begin to make noise if your oil pump begins to fail. Valve train components need to be properly lubricated as well. A bad oil pump can result in a lot of additional noise from your valve train system.

2. Higher engine temperature. Poor lubrication because of poor oil flow generated from the pump will cause friction in the engine and the engine temperature will rise. Good oil flow is essential for lubrication and reducing friction to a minimum.

3. Low oil pressure. The oil pump generates oil flow through the engine but tolerances between metal parts produce the oil pressure. Very worn engine bearings will result in low oil pressure. Thus a worn engine will have low oil pressure even though the oil pump may be fine and there is no issue with the oil pressure relief valve either. However you will also experience low oil pressure due to a failing oil pump because poor oil flow will also result in lower oil pressure.

If your oil pressure warning light has been triggered in your engine, the causes of the low pressure need to be properly investigated because the problem may not be with the oil pump. People replace oil pumps assuming that is always the problem and then still have low oil pressure because the pump was not the problem to begin with.

That depends on the type of oil warning light being displayed. There are 2 types of warning lights

1. Low oil pressure light which all cars have
2. low oil level light which some cars have.

Low OIL PRESSURE warning means the oil pressure is below minimum and when this happens there will be insufficient lubrication of many engine parts because sufficient oil cannot get to all parts of the engine it is required to lubricate. Until the cause is identified and rectified the warning light will remain. If you run your engine with low oil pressure you will cause expensive damage to internal engine components.

Low OIL LEVEL warning means the oil in the sump has dropped to a dangerously low level (which may be due to an oil leak or abnormal oil consumption by the engine.) This warning means the oil level needs to be topped up and the warning will stay displayed until you top up the oil. Running the engine with low oil will cause expensive engine damage.
Since it is a 2 minute job, Oil levels should be checked fortnightly as a minimum, together with radiator coolant and power steering fluid levels, if you run the car most days each week as most people do.

It is possible for a warning light to remain displayed when the cause has been dealt with because there is a problem with the sender unit. However it needs to be established with alternative checks that the problem has been fixed before investigating if there is a problem with the warning light itself.

Look on the engine block . There should be a wire on it to the engine ignition magneto.If the engine runs the low oil sensor is not the problem. If the oil is full and the engine has no spark try disconnecting the wire from the low oil switch if you get spark the low oil switch is bad.replace stitch and reattach wire and fill oil to proper level

Some engines come with a low oil kill sending unit which will not let the engine start when it's low of oil and will kill the engine if it runs low of oil while running.

this means a mechanical gauge test is required to check actual pressure warm idling if low below 20 psi then the oil pressure pump relief is stuck open or engine bearing are worn

it means the oil pressure is low and may be low enough to damage the engine if you keep drving/running the engine. it would help if you could tell us the actual oil pressure, engine and mileage . basically, the oil pressure may be low enough to wreck your engine, then again it may be bs......

first thing check is the engine oil level.if oil level okay check oil pressure should be for the 4.2 engine oil pressure should be 12 psi @ 1200 rpm for the 5.3 oil pressure should be 18 psi @ 2000 rpm if oil pressure good problem in the oil pressure sending unit. if oil pressure is low problem faulty oil pump or worn crankshaft bearings if oil pressure low engine will have rod knock.make sure you are using correct oil viscosity if oil too thick you will have low oil pressure oil too thin you will loose oil pressure.

it is a combanation of both low oil level =low oil pressure check your oil level and make sure it is on the full mark and drive it to see how pressure is it could also be the oil pressure sending unit good luck