QuestionHi, I had a previous question which was answered on 3/19/09, which was a backfire problem. We replaced the airbox hoses, put in all new sparkplugs because we found 2 plugs were wet, added a fuel additive, and from a cold start, it started right up. But, after hitting the accelerator for 2 minutes, it shuts off. I plan on replacing the spark plug wires and the distributor rotor. Whar are your thoughts.
AnswerHi Colleen,
It will be very easy to run out of money by replacing parts until you find what is wrong.
You need to run tests to find a problem and then only replace what is wrong.
When an engine shuts off it is for a reason, It has lost either compression, fire or fuel so all you need to do is to test to see which has went away. Compression does not usually go away and come back later so it has to be fire or fuel and it is easy to test which.
Connect up a timing light and tape the trigger down so the light flashes all the time and run the engine again to see if the light goes out before the engine stops rotating. If the light keeps flashing all the way to the crank stops turning then you know it is a fuel problem. If the light goes out before the crankshaft stops rotating then it is fire.
To test fuel you need to get a "T" fitting and put a fuel pressure gauge on the end of the "T" fitting in the fuel line. It should read about 32 PSI running and about 42 PSI (vacuum removed from the pressure regulator) Be sure to put hose clamps on the hose fittings so the pressure don't blow a hose off and spray fuel all over.
When you have it narrowed to either fire or fuel let me know and I will give you the next set of tests.
Howard
