1997 grand marquis
When I'm driving my car down the highway going 65 mph and
it drops speed and my foot is still on the gas and it slows
down do it got something to do with the air flow sensor are
Good question, could also be excessive exhaust back pressure, fuel supply limited due to a bad pump or plugged fuel filter, O2 sensors not responding correctly as well as any number of sensor problems, grounding issues, etc. I think the first thing to check would be the fuel pressure and flow, then the exhaust back pressure, if it's still acting up then a live data scan should locate the problem.
Where can I find that at under the hood
There is a test port towards the rear of the engine on the fuel rail. You can purchase a DIY kit at your local parts store for the exhaust test.
Ok appreciate it man I know I'ma be spending bout 700 to 800 dollars
At least that, if you find you need parts try aftermarket first, it could save you some money.
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