90 Ford F-150 spitting and sputtering

TRACY&KEN

MEMBER
1990 FORD F-150
6 CYL
2WD
AUTOMATIC
170,000 MILES

I have a 1990 Ford F150, 4.9L 300 straight 6. It is spitting and sputtering really bad. It started out by just kind of******** the truck really bad while driving. Then it got to where it would spit and sputter until you got to about 45 mph and then it would smooth out. Now it will crank but it keeps cutting off before you can put it in drive. We have had someone work on it this weekend, costing us about $300 and it is still doing the EXACT samething! The man changed - the fuel pump, fuel filter, spark plugs, fuel pump relay, and the fuel pump regulator. And nothing worked. He now says that it could be the timing chain. Everyone else that I talk to says that that doesn't make any sense. Does anyone know what is going on with my truck? It is our only vehicle and we really need it fixed.

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Do you have a check engine light ?

Go to this link: https://www.2carpros.com/articles/engine-hesitates

Could be one of the following below -check and test:

Oxygen sensors.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard.