Reader Question: I have a 1995 Mercury Cougar V-8. I have replaced my battery, alternator, spark plugs, and wires clean my mass air sensor and changed fuel filter.
When I start my car and but it in reverse or drive it seems like it stalls out and dies.
Also, when it doesn’t do that when I’m driving and then stop, then put my foot on the gas it seems to stall out again and sometimes dies.
I am really stumped by this. Can you help?
You might have a dirty throttle body and idle control motor. The throttle body is where the carburetor used to be on top of the engine and mixes the fresh air from the air cleaner with the fuel from the injectors.
Dirt and carbon build up within the throttle body and cause erratic idle complaints, slower starting complaints, and dying at idle and slow speed complaints. Just about any auto mechanic, even some of the fast lube places can clean these two items for you.
Cleaning the throttle body and idle motor should really be part of routine maintenance anyway and is a good idea to have them inspected and cleaned once a year.
I would also check for a vacuum leak under the hood somewhere. With the engine running open the hood and listen for a hissing noise that is caused from a vacuum leak like in a rubber hose that might have come loose or broken at the connector.
Run your hands under the fresh air inlet hose from the air cleaner to the engine and make sure there are no cuts or cracks in that hose that might cause a vacuum leak.
If you still do not see the cause of the problem I would check the fuel pressure at the engine with a manual fuel pressure gauge to see if you might have a weak fuel pump.