It's a 96 Mercury Grand Marquis with 55k milage.


Today I started the engine, then the engine stops 2 seconds later. I tried again and hold the gas padel, the engine running. Then stops right after my foot leave the padel. After 30 minutes, I tried again, the engine starts without any problem. That's the 3rd time in last couple months.


The only thing I could think of is I changed original motorcraft spark plugs to bosch platinum 2+ ones 3 months ago.


Any suggestions are welcome.

Sounds like it could be a vacuum issue, if your losing all vacuum pressure your engine will shut off. Check your PCV valve and other components involved with the vacuum. Can't be the plugs because it's firing up.

I had the SAME exact problem with my oldsmobile cutlass, as described above. I had to hold down the gas to keep it going, if not it would shut RIGHT off. Turns out my rubber gromet that kept the PCV valve in place dry rotted and the valve popped right out, cost me no more then $5.