Rough idle and stall in gear

[Cannoncore]

91 explorer sport

most of the time rough idle while in gear, sometimes its not that bad but I can always still feel it twinge. it will start to shake the car violently if sitting more than 30 seconds in gear. In park or neutral it will sort of even out a bit but with something still obviously wrong.

any ideas?

I've put seafoam in the tank but didn't help. I'm pretty new at this.

all help is very appreciated!

 

[1AJeremyD]

Sounds like you have a misfire. Most likely either a bad plug or injector. When was the last time the plugs and wires were changed?

 

[Cannoncore]

Sounds like you have a misfire. Most likely either a bad plug or injector. When was the last time the plugs and wires were changed?

unknown. but not in the 3 years I've owned it, though I do clean the plugs regularly.

is there a way to test the injectors?