Repair And Fix it

The oxygen sensors in your car perform several duties. Their primary function is to monitor and adjust your vehicles fuel mixture so that it gets the best possible fuel mileage while emitting the least amount of toxic emissions. Most vehicles have several oxygen sensors installed throughout the fuel system and engine, so the term "bank one" or "bank two" is used to identify the location of the sensor.

Age

No car part is built to last forever, and that is true for oxygen sensors as well. Over time, normal wear and tear can cause your oxygen sensor to fail. Common causes include the gases from engine emissions and buildup of naturally occurring engine deposits.

Chemicals

Oxygen sensors can be damaged by bad gas, leaded gas, internal coolant leaks, burnt oil and even products that have been applied to other parts of the engine to fix problems, such as gasket sealers. Oxygen sensors are really only meant to be exposed to good quality fuel, so other additives or chemicals can cause them to stop functioning properly.

Heating Circuit

Most modern O2 sensors have an electrical heating circuit built into the sensor. If the electrical heating circuit malfunctions or fails, it is not uncommon for the entire oxygen sensor to fail.

Battery cable corrosion occurs for many reasons, not the least of which is oxidation, a process hard on humans and metal objects. This especially applies to batteries and cables that add corrosive acids and chemicals to the mix. Besides the composition of the battery, another consideration is the battery posts and cables. Mixing dissimilar metals or certain metals together quickly leads to corroded battery cables.

Galvanic Corrosion

A major cause of corroded cables is the mixing of two dissimilar metals when securing the cable to the battery post, which creates a galvanic reaction between the two metals. Three things must be present for this type of reaction: two dissimilar metals with different electrochemical signatures; an electrical path; and a path for metal ions to move from one metal to the cathodic metal. With this two-way path available -- which is how car batteries work when immersed in an electrolytic solution such as sulfuric acid -- a miniature battery develops with current flowing in one direction and the metal ions moving to the stronger metal. This process forms the corrosion seen around the batterys post and cable end.

Battery Fumes

Any kind of venting of battery fumes in or around the battery cables will cause corrosive buildup on the cable ends. This happens when battery cell covers arent secured tightly, or theres a crack in the battery casing, allowing fumes to escape. When corrosion occurs, your battery has to work harder to provide the amperage necessary to start the car. Corrosion that continues to grow can make its way inside the battery and effectively destroy its ability to hold a charge.

Battery Acid

A cars battery contains acid. Besides helping the battery work to store electricity, sulfuric acid acts as a catalyst for corrosion. The acid, when combined with the environment under the hood -- anti-freeze fumes, grease, oil, humidity, dirt and oxygen -- accelerates the corrosion process. Battery cables made from copper are particularly susceptible to corrosion when in contact with sulfuric acid and oxygen.

Prevention

To aid in prevention, ensure cable ends are the same metal as the battery posts. Clean the battery posts with a metal terminal cleaner. For tough cases, use a water-and-baking soda mixture to remove the corrosion, but dont let this concoction enter the battery; this will cause battery failure. Use the brush end of a battery terminal cleaner to hone out the inside of battery cables. After cleaning, apply dielectric grease to the battery posts and cable ends to prevent corrosion buildup. Replace any battery cables that have exposed wires or tears in the sheathing -- these promote corrosion where you cant see it, inside the sheathing itself.

Safety First

When working with a battery, practice safety. Dont smoke around batteries, especially those with the cell covers off; this could lead to explosions. Dont over-tighten battery cable ends -- you could break battery posts. And remove the negative terminal connection before removing the positive to avoid sparks that can ignite fumes.

Exhaust Burble on Acceleration

Some cars exhaust systems will produce an odd burble or bubbling noise. For the most part this is deliberate when it occurs in vehicles upon acceleration, but not always. Many "street racers" and similar cars have undergone a few modifications to give them better fuel efficiency at higher RPMs. In order for this to occur, the lifters and timing mechanism for the sequence of combustion in the engines cylinders is altered. This means that, while the engine timing will work well at much higher RPM, the combustion process at lower speeds is slightly off. The burble is in actual fact a series of lean misfirings caused by this timing which rumble out through the exhaust system. It causes no serious damage to the engine, and soon disappears once the vehicle has reached high speeds.

Exhaust Burble on Deceleration

An exhaust burble, or throaty popping noise which could be likened to a babbling brook, is has a different cause if it only occurs when suddenly backing off on a vehicles throttle. Essentially, the sudden easing off the throttle causes an immediate decrease in exhaust emissions to the degree that atmospheric pressure surrounding the exhaust pipe pushes cool air up into the exhaust system. This air collides with the warm exhaust gasses and creates a rumbling not unlike thunder. Normally this will only happen if the tailpipe has too wide a diameter to maintain equalized air pressure, or there is a seam in the exhaust pipes which is not air tight.

Repairs

Some people like having the throaty noise of an exhaust burble; some do not. For those who do not want this sound, there are ways of fixing it. For an exhaust burble on acceleration, the engine must undergo a professional tune-up including resetting the timing mechanism and lifters; keep in mind this will decrease high speed engine performance, but increase the quality of performance at low speeds. For exhaust burbles upon deceleration, the seams of the exhaust pipe must be sealed against unwanted air entry, or the pipe must be swapped out for one of a smaller diameter to maintain equalized pressure between exhaust and the surrounding atmosphere.

A flex plate is basically a molded piece of thick sheet metal that is used to connect the engine to the transmission. Even though flex plates are built keeping their exposure to heat and corrosion in mind, they tend to get warped many times due to a variety of factors. A warped or bent flex plate can cause serious damage to the engine assembly, making it imperative to replace any warped flex plate as soon as possible.

Improper Installation

A flex plate will bend if the flex plate assembly is not installed at a right angle to the crankshaft flange. Flex plates also get warped if the engine or the torque converter is out of balance as it increases the overall weight on the flex plate.

Improper Bolt Fittings

Improper bolt fittings is the most common reason for flex plates to warp or crack. Loose mounting bolts, improperly connected flex plate and torque converter bolts can cause flex plates to warp. Even during maintenance, if the mechanic fails to follow the proper sequence (removing the torque converter and flex plate bolts before removing the engine or transmission bolts), this invariably leads to a bent or warped flex plate.

Bad Starter Drives

An improperly installed starter drive can cause the flex plate assembly to rapidly wear off leading to cracks or a warped flex plate. Also, some starter drives may require the use of starter shims. If these shims are absent when the starter drive is employed, this will lead to improper alignment of the flex plate and cause it to bend over time.

Other Causes

Flex plates may also get warped due to worn-out pump bushing in the transmission. Also, crankshaft wear and tear can also eventually lead to a warped or bent flex plate.