Fuel, Spark Tests Needed on Engine Shut Down Problem

October 10, 2009/All Used Car Sales

MOTOR MATTERS ASK THE AUTO DOCTOR BY JUNIOR DAMATO

Dear Doctor: My 2002 Suzuki Grand Vitara has over 62,000 miles and I had to have the timing chain replaced. Since then it suddenly shuts off and the dashboard lights come on. While driving on the parkway at 60 mph my daughter had no gas pedal. She had to steer to the shoulder and turn off the engine. It started up after a few minutes. One day I drove two blocks, stopped at a stop sign, turned, and went about 50 feet and then the SUV quietly stopped. Within a few seconds it started by itself. What should I do? Mary
Dear Mary: You will have to have a technician hook up a fuel pressure tester and a spark tester to the SUV. You will then need to drive it and monitor the tester and fuel pressure and see what the engine loses. Once the source of the power loss is determined, further testing will need to be done on that failed system.
Dear Doctor: My mechanic fixed several problems on my 2003 Ford Focus. The alternator, battery, ignition coil, and spark plugs were changed. The car ran better but later that day the “check battery” light came on. The new alternator is only charging to 12.5 volts, the car is cutting out intermittently and the dash lights will begin to glow dimly just before the engine dies. I let the car sit for half an hour and it started back up again with no problems. I need your opinion. Chad
Dear Chad: There is no question that there is a positive or negative connection problem somewhere in the system. A technician will need to start at the battery connections and follow to the engine ground, as well as all of the wiring to the starter and solenoids. The technician will have to use a voltmeter — not a test light.
Dear Doctor: I own a high-mileage 1988 Toyota Camry that has a hard time starting in the morning and after it has been idle for more than a few hours. I performed a tune-up, which included the cap and wires, plugs and the gas filter. That is when I noticed oil in the #1 plug tower and the plug seemed to have some oil on the electrode. About a month later the engine died and I had to replace the ignition coil. I still have the hard-start condition. What should I do? Tom
Dear Tom: First, I would like to see you check for any trouble fault codes in the computer.

2002 Suzuki Grand Vitara

Then check the operation of the cold-start injector and timer. I’ve also seen coolant sensors out of specification that may cause this problem.
Dear Doctor: I own a 2008 Buick and 2009 Honda. Both have oil life monitors. I spoke with both dealer service departments and they said there is no need to change the oil until the monitors say it is needed. I have always had the oil changed at 3,500-mile intervals. They now say 5,000 miles is the average. What do you think about the longer intervals? George
Dear George: Oil quality has changed over the years and combined with cleaner burning fuel injection engines oil now runs higher temperatures. Oil can now go for longer intervals without harming the engine. Some import vehicles recommend only an annual oil change. But I still like to see the majority of oil and filter changes using regular oil at 3,000 miles; synthetic blend at 4,000 miles; full-synthetic oil at 5,000 miles. My recommendations are earlier than manufacturer recommendations. I make that statement based on what I’ve seen by actually working hands-on with vehicles after they come off warranty.
Dear Doctor: I own a 1997 Volvo. The odometer and trip odometer stopped working, however the speedometer still works. What can be wrong? Allan
Dear Allan: The speedometer is working off a signal from the vehicle speed sensor. The other odometer parts have an internal failure. There is a company in Taunton, Mass., called BBA Remanufacturing that we use for odometer failures, as well as many other electronic dash and module failures.

Junior Damato is an ASE-certified Master Technician.

E-mail questions to [email protected]

Mail questions to: Auto Doctor, 3 Court Circle, Lakeville, MA 02347

Listen to Junior online at www.1460wxbr.com Saturdays from 7 a.m. to 10 a.m. eastern time.

Copyright, Motor Matters, 2009