Expert: Vern Bullock - 9/21/2008

Question
Hi! I was driving my usually very reliable 64 Dodge Dart Wagon (225 slant 6) on the highway and suddenly the whole vehicle began to shake and felt like the engine was going to shut off.  It only happened for a moment and then ran like normal again.  Within a few more miles the symptoms repeated and I pulled off the freeway and shut the engine off.  I had just filled up with gas so I checked the oil.  It was low but nowhere near empty so I added a quart to see what would happen.  I tried to start the car and it would no longer start.  It tried to turn over; when I got a tow I looked at the ground and saw a lot of oil (about 1/4 quart) in many different spots directly beneath the engine block.  Recent repairs include: new alternator, battery, starter, voltage regulator, repacked bearings, spark plugs & wires, speedo cable, oil change.  I have done plenty of driving since all of these repairs were done and have not noticed anything unusual.  Sorry this is so long, I wanted to provide as many details as possible, like you specified! Before I tear all of my hair out can you offer some possible diagnostics...oil pan gasket leak? oil pump?

Answer
Hi Bonnie:
Lots of details are good, especially with a problem like yours. Your symptoms are a bit unusual, but the first thing I would look at is the motor mounts. Sounds like one may have broken loose. If this is true, you would feel more shaking as you accelerate and less as you decelerate or drive at a constant speed.

If this was not the case, then the problem may be elsewhere. If you recently filled up with gas and there was trash in the gas (e.g. the gas station just refueled just before or while you were there), the station could have introduced trash into your tank from the pump. If this sounds like the problem, then dumping the gas tank and replacing the fuel filter will be required.

The fact that the problem occurs randomly, the above are the two top causes. After letting it sit for 24 hours, tell me how it drives. That information may be of additional value.