Question: My 1980 Rabbit diesel, whenever it wants, sucks oil from the crankcase and burns it up in the engine. When this occurs, the engine races to full throttle, chatters very loudly and blows clouds of black smoke out of the exhaust. My mileage is 75,000. I sure hope you can think of something.--G.A.N.
Answer: Some Rabbits of your vintage had problems with a buildup of pressure inside the crankcase, which would cause oil to blow through the crankcase ventilation system and into the engine.
Every engine has a crankcase ventilation system, which is designed to vent out gases that blow out of the combustion chamber past the piston rings. The positive crankcase ventilation (PCV) valve handles most of the gas, but sometimes a secondary bypass hose is added.
The Volkswagen fix is to install a bypass hose from the valve cover to the air filter housing, providing additional ventilation for the crankcase.
A Volkswagen dealer should be able to check your serial number and determine whether your engine is one of those that was designated for the repair. If it is, the installation is covered under an extended warranty.
Since you say the problem is intermittent, you may also have a specific problem that is causing excessive blow-by of engine gases into the crankcase. It probably makes sense to have an engine compression and pressure test done.
Q: My 1983 Pontiac Trans Am has a problem with a sticking gas pedal. It has a five-speed transmission and a cruise control. I have had the accelerator linkage greased and have replaced the servo-vacuum diaphragm, but the problem still persists. When the stick occurs, I immediately place the car in neutral and turn off the engine. The dealer can't find anything wrong. Do you have any suggestions?--M.L.G.
A: The best advice I can offer is that you have a first-class safety problem that needs immediate attention. If one dealer can't fix it, you should find one with properly trained mechanics who will fix it.
Your Pontiac has a cable-operated accelerator linkage. The cruise control is operated off of the speedometer cable from the transmission.
If neither of those cables is binding, then the next logical place to look is the servo-vacuum unit, which is the device that provides the electronic logic, vacuum power and mechanical control for automatically setting the throttle on the carburetor.
On a problem like this, you can bet a responsible dealer would exhaust every resource before he shoves the problem back at you with an excuse. All Pontiac dealers have direct lines to technicians in Pontiac, Mich., and a sticking accelerator is the kind of problem that should send them to the telephone.