What could be wrong with a Nissan Altima that cranks but wont start?
The fuel pump fuse is blown or the fuel pump has failed.The crank position sensor has failed. Turn the key to "Run"Listen for the fuel pump to run for a few seconds then stop.If you don't hear the pump run:1) Turn the ignition key to the "Off" position and remove. Check the fuse in the engine bay fuse panel. This is a panel encased in a plastic box and usually has "FUSES" printed on the cover. Inside are high draw, high amperage fuses and relays for things like the fuel pump. Find the pump fuse, pull it and look to see if it's good. If it's blown, replace it with same amp rating fuse. Check again to see if you hear the pump run. If it does, you're lucky. Press on. Car should start. If the pump still doesn't run then see 2 below.2) If the fuse is good, then it's a good chance the pump has failed. You will have to tow the vehicle to the shop; it's dead in the water.If you hear the pump run and the car cranks but will not start, chances are it is the Crank Position Sensor (CPS). The CPS feeds info to the engine management computer telling it the crankshaft is rotating and to allow fuel flow and ignition to occur. If the computer doesn't get the CPS input, the car will not start. Again, dead in the water and a tow to the shop.Just had this experience on my '98 GMC pickup ...good pump, engine spins, no start. A flat bed ride to the local shop and ...ta-da! ...OBDII code reads CPS malfunction. Four hundred and some odd bucks later, she's up and running like a top.
What could be the cause of a car’s temperature gauge to fluctuate?
There are several possibilities.1) faulty teperature gauge. In this case the gauage will have to be replaced. This is relarively simple and inexpensive depinding on the make and model of the car.2) Issue with the radiator, coolant of the car. This could be caused due to insufficient coolant, leakage of coolant, damage to the radiator of the car. This will require extensive repair. In this case, it is advised to get the issue diagnosed and fixed at the earliest to avoid engine damage due to over heating.Hope this helps. :)
What causes a car to lose power while driving?
In modern cars with engine management systems, it is the system itself that reduces power if it detects a problem with the engine. A warning light will come and and the engine will go into 'limp home' mode, where speed it usually limited to 80km/h or lower. Any number of things can cause this, but usually it relates to loss of something important, like a coolant leak, or low oil pressure. Sometimes it can also be a false positive due to a fault in the management system itself.All internal combustion engines require three things to work; compression, fuel and ignition. Degradation of any one of theses will result in lower engine performance.Loss of compression can result from engine wear, common in engines with several hundred thousand kilometers on the clock. Engine efficiency is lost because gasses can escape past the piston rings. Mechanical failure such as a blown head gasket can cause a similar loss.Blockages or degradation of the fuel supply, such as a worn fuel pump will cause loss of power for obvious reasons.Ignition faults stem from things such as a cracked distributor head, worn spark plugs, worn ignition coil or faulty spark plug leads. They generally result in some cylinders not igniting the fuel/air mix, thus reducing the power.Loss of lubricant or coolant will cause the engine to overheat and then seize. In this case, loss of power is 100%.Worn bearings in the engine will usually not reduce power much, they will keep working, making more and more noise, and then fail catastrophically, causing the engine to seize.It is also possible for timing chains to slip, adjustment screws to loosen in the carburetor, exhaust manifolds to develop leaks , and other minor mechanical faults to occur that will reduce engine power. This can happen suddenly or gradually over time.
What is overdrive and how should I choose between putting my car in drive or overdrive?
All the answers here are good for describing what overdrive does, but don't really give examples as to when you should use or not use overdrive.Most have said overdrive is good for highway use to reduce the RPM's of the engine and therefore conserving fuel. This is true as that is what it was designed to do.Additionally, overdrive would be safer in slippery situations where ice or wet roads may be a factor as the drive wheels would be much less likely to see a sudden acceleration from loss of grip.However, when do you not want to use overdrive?A good rule of thumb for this situation is to compare it to situations where you would find it beneficial to down shift in a manual transmission.These may include:When you are preparing to switch from a slower moving lane of traffic to a faster lane. Passing. Extended downhill grades, to prevent having to ride the brakes.Extended uphill grades to maintain power Hills when you are having trouble maintaining speed.Curvy roads where engine braking would be beneficial.TowingHopefully this helps.