The Online Mechanic » 2007 » March

Automotive help for amateurs
Mar
25

Comment:
i have a 1979 Jeep Cherokee .i just recently changed my alternator due to falty bearings, i checked the voltage before i changed the alternator and it was reading 14.35,i replaced the belts before i went out to buy one. and it still was squealling so i replaced the alternator  with a rebuilt one. and it only charged at 12.25 and it squealls very loudly. the battery was charged over night on a trickel charge and tested good, i adjusted the belts, but the tightest was the 12.25 reading. i took the ground wire off the battery and the squealling stoped but the reading from the alternator was 16.45. this is the second time i replaced it in two days with the same problem. my old alternator charged good but squealled, my two new alternators squeall and charged bad. could it just be two bad alternators? or a grounded wire?
    If this happens to you, check to see if you have an external voltage regulator. The new alternator could have over loaded the old one and caused it to malfunction. I have run into a situation where I replaced a rebuilt electrical part twice and both were bad but that would be rare. Also check to see if the wires were connected correctly and that you don’t have any bare wires touching.



Mar
18

Name: Craig Wilson | E-mail: autofix@aapt.net.au | URI: http://www.autofix.com.au | IP: 59.100.23.38

Hi,
First let me introduce myself, my name is Craig Wilson and I operate Autofix.com.au. As my experience has only been on Australian cars and most of my traffic comes from the U.S. I’m on the lookout for someone I can refer my visitors to if I can’t answer their questions. Would this interest you? I feel the benefits would be mutual as I can help people find a solution, whether on my site or not and you will see a good traffic increase. If you are interested please email me, if not I understand and all the best to you.
Regards
Craig Wilson

Craig: I recently had to give up on being a mechanic due to health reasons but I haven’t given up on cars as of yet. I have a son that is an ASE certified auto mechanic who keeps me up on what is changing in cars.I would enjoy linking up with you. It might take a couple of days if I don’t get it right on firdt try as I am new to all this blog stuff. I have an internet savy son who can help me later this week. Look forward to hearing from you.



Mar
18

Name: Ahmed | E-mail: ahmedas617@yahoo.com | IP: 193.133.99.236

I have a 2002 V6 30V Passat. It developed gear transmission problem.
Initially, the gear shifting was not smooth. Changing to second gear was abrupt and same when shifting to other gears. When vehicle is stopped and restarted, the shifting will be smooth, but as soon as car speed reaces about 40mph the same thing will come back.
However,it has worsen that when car is started it comes with a squeeky noise and when shifted into drive gear does not engage into drive gears, but will engage into reverse gear.

Ahmed: I would first check the transmission fluid level. If it gets low your trans will slip or not work at all. Start with that and if it is full it sounds like you have some problems inside your trans. The newer cars are using electrical cylinoids to shift the transmissions now and it sounds like you have one malfunctioning. I would suggest taking it to a trans shop (make sure you go to one where the mechanics are ASE certified) and have them scan your car for any transmission codes that have been set. Your car has a computer that keeps up with any problems that are going on including the trans. Any good shop will have a scan tool to check it for you. There is usually a small diagnostic fee but it would be better to check it first before letting someone sell you a new trans. 



Mar
16
By: richard | Discussion (3)

How does a car’s thermostat work?

A car has an engine that creates a lot of heat that has to be gotten rid of and at the same time regulated so that the engine will perform efficiently and cause the least amount of air pollution. To accomplish this the car has to have a cooling system that will not only get rid of the heat, but maintain a reasonably constant temperature. In addition, the cooling system has to provide heat to the interior of the car to keep it warm in the winter.

The cooling of the engine and heating of the car is done by using a liquid that can carry the heat from the engine to a radiator where the heat can be dissipated into the air and to a heater core that transfers heat to the inside of the car. This liquid is carried from the engine to the radiator and heater core through hoses and inside one of the hoses is a device called a thermostat. The thermostat controls the flow of the liquid by opening and closing depending on the temperature of the liquid running through it. The thermostat creates a temporary blockage in the hoses that carry the liquid. Doing this causes the liquid to rise in temperature so that the engine will run more efficiently (an engine runs most efficiently at about 200 degrees Fahrenheit) and your heater will be warm enough to heat your car.

A cars thermostat is a round metal device that has the center of it attached to a metal coil that expands or contracts depending on the temperature of the liquid around it. It is located in the engine and when the temperature of the liquid in the engine reaches approximately 200 degrees Fahrenheit the metal coil expands and opens the center section of the thermostat to allow the heated liquid to flow to the radiator or heater core where the liquid is cooled. As the liquid in the engine becomes cooler the metal coil contracts and slows the flow of the liquid which in turn raises the temperature of the liquid. The metal coil is designed to open the thermostat just enough to keep the engine at about 200 degrees Fahrenheit.

If you have ever driven your car and the engine has over heated, the most probable cause is the thermostat has stuck closed. Or if you have driven around on a cold winters day and you heater just won’t heat up, then your thermostat is probably stuck open.



Mar
04

Question: I’m not sure if this the correct place to ask the mechanic a question. I have a 2001 solara. It makes a loud squealing noise, when the car is cold is really bad. I had the water pump changed. It noise doesn’t change when i turn the wheel, but does stop some when i put it in gear. Once the car is warm(2 minutes or so) the noise stops. Could it be my power steering pump? please help. Thanks. 

Answer: Sounds like you have a loose alternator belt. When you first start a car it uses power from the battery and the alternator initally has to work a little harder to charge the battery back up. If the alternator belt is loose it will squeal until the battery charges up.  Could be who ever changed the water pump didn’t tighten up the belt or the belt tensioner is weak. u

 



Mar
03

Question:
I let my 96 blazer run out of gas and now i cant get it started back any ideas

Answer:
Michael: Make sure that you have 4 or 5 gallons of gas in the tank. Raise the hood and find the fuel check valve on the fuel rail. It looks like an oversized tire valve. Have someone try and start the vehicle while you press in on the valve. Keep your face out of the line of fire in case gas sprays out. If no gas comes out then try banging on the fuel tank with a heavy object. If you use a hammer, hit the tank with the flat side of it to keep from denting the tank. You might have to hit it several times. What you are trying to do is wake up the fuel pump. Try it and see what happens. Get back to me if that doesn’t work. Good luck.



Mar
03

Question:
I let my 96 blazer run out of gas and now i cant get it started back any ideas

Answer:
Michael: Make sure that you have 4 or 5 gallons of gas in the tank. Raise the hood and find the fuel check valve on the fuel rail. It looks like an oversized tire valve. Have someone try and start the vehicle while you press in on the valve. Keep your face out of the line of fire in case gas sprays out. If no gas comes out then try banging on the fuel tank with a heavy object. If you use a hammer, hit the tank with the flat side of it to keep from denting the tank. You might have to hit it several times. What you are trying to do is wake up the fuel pump. Try it and see what happens. Get back to me if that doesn’t work. Good luck.



Mar
03

Question
I have a VW Jetta 2003 1.8T and every time I turn on the heat/fan it makes a weard squeeking noise but only when it on. The when i turn it of it stops. It also makes it when i have the heat or fan on and i take a turn then it makes a little louder sqeeking noise.
PLEASE HELP

Answer
David: Sounds like you might have one or two problems. A worn heater fan can make a squeeking noise if the bearings in the fan motor are going out. It also could be a fan belt squeeking due to the extra electrical load you are putting on the motor. Determine where the noise is coming from. If it is the fan it will be coming from under the dash on the passenger side. If the noise is from the fan belt, raise the hood and lestin for belt noise. Personal experience on bad heater fans. My dad’s heater fan locked up and didn’t blow the fuse. The electrical wiring over heated and caught his truck on fire and it burnt to the ground. Good luck.