AUTO REPAIR
Basics on fuel injection
Q: I’m hoping you can bring an old-timer up to speed on fuel injection. I used to be pretty good at fixing things but hadn’t even considered trying to work on this one. I’d feel better driving if I had an idea what’s going on under the hood.
A: A typical fuel-injection system uses three general processes: fuel pressure, thinking/processing and fuel delivery. Fuel pressure involves the use of an electric fuel pump inside or near the fuel tank. The pump sends fuel to the fuel rail, a pipe of sorts that’s attached to the engine and the fuel injectors. There, a pressure regulator holds a specified pressure and returns unneeded fuel to the tank. Recent vehicles house the regulator in the fuel tank and send forward only the fuel that’s needed.
The thinking/processing part employs a control unit typically called an electronic control module/powertrain control module, or ECM/PCM. In addition to managing the fuel pump, this very smart box receives information from a dozen or more engine and transmission sensors. This information indicates engine and vehicle speed, load, temperature, airflow, throttle position, altitude and gear selection, just to name a few. Incoming data is crunched with programmed instructions resulting in appropriate commands being issued to fuel, ignition, transmission and emission-control actuators.
Fuel injectors manage the delivery of metered, misted fuel, which next vaporizes in the intake manifold on the way to the engine’s combustion chambers. Each brief electrical pulse sent from the ECM/PCM to these electromechanical showerheads results in a precise shot of fuel just as each intake valve opens. Very recent vehicles take this a step further and shoot highly pressurized fuel directly into each combustion chamber.
Fuel-injection systems are incredibly reliable. When service is needed, a scan tool provides access to trouble codes, sensor data, fuel trim or fine-tuning information, actuator commands, the data snapshot and additional diagnostic information. Fuel pressure may also be checked by connecting a pressure gauge. Typical problems, while very rare, include a worn-out fuel pump, with a lifespan perhaps of 100,000-150,000 miles; dirty fuel injectors; and sensor or connection faults. Most are fairly easy to diagnose and repair.
— By Brad Bergholdt
McClatchy-Tribune News Service
REAL ESTATE
Short sale worries ex-fiance
Q: My ex-fiancee bought a home, and over time I took over payments and was given half ownership. The property now is “underwater,” and she wants to do a short sale. The loan is in her name only, but the deed is in both of our names. What are the ramifications of a short sale for me?
A: Because you are not on the loan, this shouldn’t be an issue. You still have all of the obligations to your buyer as far as disclosure and fair dealing, but the short sale should have no effect on your credit score.
You may be required to submit some information and sign paperwork from the lender. Carefully review anything that you sign to ensure you are listed as a nonborrower.
For owners who were married, the rights and responsibilities are dealt with during the divorce. When the owners aren’t married, there is no such process for resolving issues in case they decide to split.
When buying property with another person, it’s very important that you have a written real estate agreement prepared in advance that addresses the operation of the property and the disposition of the property in case the relationship falls apart.
— By Gary M. Singer
Fort Lauderdale Sun Sentinel