Reasons a vehicle will vibrate
Q. I have a 1996 Honda Accord and from time to time out on the highway the car just starts to shake. If I slow down, it usually goes away. In the past, if I had a vibration, it was usually caused by a tire or balance problem and the steering wheel shook.
Any thoughts with this old car. It still runs great and I want to hold on to it.
A
. I would start with a thorough inspection of all of the tires and the suspension. I would look carefully at the rear suspension, especially the bushings, joints and sway bar. A tire that is slightly out of balance combined with any excessive movement/wear could cause this vibration.
Q
. I have an old car that hasn’t been run in years and I want to get it going. So far, I have charged the battery, it has spark and fuel but still won’t start. Any ideas?
A
. Someone recently asked me to look at a car that also hasn’t been run in a while.
Like your car the battery was OK. There was a spark at the plugs, but the car wouldn’t fire up even with starting spray. I pulled the spark plugs and they were somewhat fouled, which certainly would cause hard starting. Then I asked how long it had been parked.
The answer shocked me. The owner thought five or so years, but in reality, it may have been several years longer. The problem was a combination of fouled spark plugs and gasoline that has gone stale. Flushing the gas tank, replacing the fuel pump and the spark plugs made this engine run like new again. Even though the engine ran well the work wasn’t done yet. The cooling system, brake system transmission and suspension all need to be checked before it is road-ready.
Q
. I have a 2001 Dodge Caravan that I use for flea markets and the heater isn’t working.
I’m trying to save a little money and do some of the diagnostic work myself to find out why there isn’t any heat coming out of the heater. The first thing I did was replace the thermostat, but that didn’t change anything. One concern that I read about online was a cylinder head gasket leak. The engine never seems to use antifreeze so I’m hoping that is not the problem. The ducts and blend door seem to work. I have a thermometer and the temperature going in and out of the heater hoses is about 185 degrees. Any thoughts?
A
. A leaking cylinder head-gasket is a possibility. The heater system can get air-bound and stop hot water circulation. The cylinder head gasket issue can be ruled out by using a “blockcheck” kit that looks for exhaust gas in the cooling system. If you can find a shop with an exhaust gas analyzer, a hydrocarbon reading at the radiator will also tell if there is a problem. You didn’t mention if you flushed out the heater core. It is possible that there isn’t enough coolant flow through the heater core.
Q
. I have a 2007 Hyundai Santa-Fe, which is the best vehicle that I have ever owned. It has only one problem. When I try to fill the gas tank the gas pump keeps shutting off. It does this if the tank is nearly empty of nearly full. Once I do fill the tank, then the engine doesn’t start or starts and stalls. Any ideas what is going on?
A
. More than likely the issue all centers around the evaporative emissions system. Mounted on the back of the intake manifold is a small valve, with an electrical connection and two hoses. This valve is called a purge valve. During refueling the defective valve is allowing fuel into the engine and flooding the engine, causing hard starting. The valve is a little awkward to reach, but is a simple and relatively inexpensive repair.