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2003-2004 Infiniti G35 Sedan Troubleshooting
A sports sedan manufactured in 2003-2004 by Infinity
Car running poorly; Check Engine, Brake, Slip, and/or VDC lights are on
Car turns off while driving at low speeds, and it just doesn't run the same as before
Low brake fluid
Before looking into anything complicated make sure you're not running low on brake fluid. Low brake fluid may cause the VDC, brake and Slip lights to turn on. The car might not stop as efficiently as it did before, but sometimes that isn't noticeable unless you are trying to figure out if it takes longer to stop. You can check the brake fluid by opening up the hood and looking for the cap that reads "brake fluid". There is a minimum and maximum shown on the container. If the fluid is at it's minimum, you will need brake fluid. Now the question is what causes low brake fluid? Well it can be as simple as getting your brake pads installed incorrectly. If the rotor is damaged by one of the bolts or the bolt is incorrectly tightened, your brake fluid might start to leak.
Crankshaft Position Sensor Malfunction
If the car seems to have normal brake fluid and doesn't have any problem stopping as efficiently as it did before, you may have a Crankshaft Position Sensor Malfunction. Don't panic! It sounds complicated and costly but it'll only be costly if you chose to take it to the shop. The crankshaft position sensor is located between the engine and the transmission near the front driver's side wheel. It is possible the Crankshaft Position Sensor is just loose and needs to be reattached. In that case you would just pop it back in and tighten the bolt to keep it in there. Unfortunately that usually isn't the case. You would most likely have a burnt out Crankshaft Position Sensor and would need to replace it. There has been a recall on this vehicle for faulty Crankshaft Position Sensors, so this will most likely be the case if you haven't ran into the problem once before.
It is possible that you have a bad engine. Now this is a worst case scenario and it usually isn't the case, but it is a possibility. If this is the case, your car would be running unbearably bad and turns off at every other corner. Unfortunately if you have a bad engine you would need to rebuild your engine which would be very costly and extremely difficult to do yourself unless you own a shop. Even then, the cost of the parts is overwhelming. I suggest you evaluate the value of your car before rebuilding the engine; it may be a better idea to sell the car to a mechanically inclined individual and buy a new one.
Loud clunking/clicking/scraping/screeching in the wheels
Car wheels keep making weird noises
Low Break Pads
If the sound you hear in your wheels is a screeching sound every time you use the brakes it is most likely that you have run low on brake pads. Some Manufacturers use this as a warning for drivers to tell them "hey your brake pads need to be changed as soon as possible".
Worn out rotors
If you needed to change your brake pads and didn't do it you might have a bigger problem on your hands. After the brakes are worn out there will be metal on metal contact causing a grinding or scraping noise. This causes the rotor to get scratched and not work efficiently when you replace the brake pads. So now you need brake pads and new rotors.
Debris in the wheel
If you hear a clicking or clunking sound in wheel you may have one of two problems. The first is that you may have debris in your wheel. This isn't too serious of a problem unless it is a part of the wheel itself, which leads me to the second problem. If you had your brake pads changed recently the person that changed your pads might not have done it too well. By simply not screwing in the bolts correctly, the bolt may become loose. One loose bolt may lead to another. Next thing you know your wheel is popping off at 50 mi/h. So if you hear any of these sounds you must take it to a shop as soon as possible.
The steering wheel doesn't control the wheels and is hard to turn
The car feels weird and isn't being controlled by the steering wheel
If you have those symptoms and you have the music on, turn it off and try to hear if there is a flopping sound in one of your wheels. Pull over and check your wheels out because you may have a flat tire.
Broken steering shaft
If there is no noise from the wheels then it may be your Intermediate Steering Shaft. If sometimes it feels normal and others it's impossible to turn the steering wheel then this is your best bet. If you have a rough driver in the family and you all use the same car then you may have just found the cause of the problem. The Intermediate Steering Shaft can break if you make abrupt sharp turns.
The Check Engine/Service Soon light is on
I don't know what the problem is but the Check Engine light is on
You may just need a routine oil change. If the oil has been in your car for over 3k miles or over 3 months, you may need a change. This all depends on what kind of oil you use and how much you drive.
A check engine light can mean absolutely anything in a car. If nothing abnormal is happening to your car then you wouldn't have a clue to what it may be. That's why there is a device that can be used to figure out the problem. Once the device has figured out the problem you may move on to buying your needed parts or just fixing whatever it is that has gone wrong with the car.
Car is overheating
The car has smoke coming out of the hood
Your car may be running low on water. This is a simple process to fix if it hasn't gotten too bad. You need to service your car every couple months to make sure it has no leaks or deficiencies. You may have a leak in your water tank or you may have just forgotten to fill it up and have taken it on a long drive. It is encouraged to use a certain kind of water for cars not just tap water so it doesn't freeze during the winter. Tap water may hurt the vehicle because of the minerals inside the water, so in case of emergencies try using distilled water if available. Take it to the shop immediately to have it flushed and replaced with the right fluid.
Insufficient oil in engine
The oil in the engine keeps the engine well lubricated and cool. If you don't have enough oil in your engine your car might start to heat up.
You may have a broken radiator fan that needs to be replaced. Just like in computers cars have fans to keep them cool because they do a lot of work and generate a lot of heat. A broken fan may cause your car to overheat. The fan in located in the engine compartment near the front or back of the radiator.