More About Points »
There can be many locations where coolant can leak in the engine compartment on this car like broken hose, a loose fitting to an hose or bad radiator and for those with turbos the turbo housing & associated hoses and pipes. A good mechanic will have dyes that can put into the coolant to allow them to see the leak location with a UV light.
I assume you are saying that when you put you foot on the brakes it makes noises. There are many things that could be cause of the and most like it is worn out brake pads or shoes and need to be replaced soon. The other is brake dust that can make noise under certain conditions.
Your valve cover gasket is leaking oil into the spark plug wells thus causing your engine to idle rough & have bad fuel economy, If you are do-it-yourself, you can go to an auto part store to get a replacement valve cover gasket (which should include the spark plug well gasket) and get some form-a-gasket paste. Also you need to replace the spark plugs and spark plug wires since they are soaked with oil. First to cool you engine down and mark your firing order on the distributor cap (remember 1 at the timing chain end). Disconnect the valve cover breather hose from the air cleaner hose. Then remove the valve cover and remove the old gasket and form-a-gasket & remember to keep the nuts. Clean up as much of the oil from the spark plug wells with the spark plugs still in and clean up the oil from the valve gasket areas. Remove the old spark plugs and clean up what oil is left in the spark plug wells. Replace the spark plugs with new ones and tighten properly. Put a thin layer of form-a-gasket on the areas where the valve cover & spark plug well gasket will contact. The put some some form-a-gasket on the valve cover where the valve cover & spark plug gasket will contact and then put the valve cover & spark plug gasket on the form-a-gasket so the form-a-gasket will gaskets in place while you put the valve cover back on the engine. Remember to tighten the valve cover nuts finger tight first and then proper sequence & torque. Replace the spark plug wires to the spark plug and connect to the distributor in the proper position. Check you engine oil level and add oil as needed. Start your engine and check for oil leaks.
R134A. 1993 Nissan Altima was the first cars the have R134A AC units
You can try to check the Mass Airflow Sensor which the electronic device between the air cleaner and engine. You can try to clean the sensor and connector with residue-free electronic cleaner. I hope this helps.
The valve cover gasket gets old and start to crack and allow oil to seep through the spark plug well. Get a replacement valve cover gasket and get some chemical gasket paste (like Form-a-gasket) to help you hold the gasket on the valve cover while you put the valve cover back on, otherwise the gasket will just drop when you attempt to put the valve cover back on. Also make sure to put the nuts in the proper pattern and torque.
I am experiencing the same thing now and I'm trying several things. I remember that the Mass Airflow Sensor and associated connector was bad and it was replaced awhile back but now I'm again experiencing the same thing so I heard cleaning the sensor and connector may be able to help it. I hope this helps.
I agree with irvtech. Also wind will affect gas mileage because any serious headwind can take several miles per gallons off.
Yes you can mix most synthetic oils with "regular" oil as long the viscosity are the same . Read the label of each type oil to make sure.
I can be the window switch which I have replaced before. If you replaced the window switch and it is still "sluggish" then the window motor casing is broken and then need to replace the window motor regulator mechanism.