Stang0005

My 2000 GT has recently started to jerk while accelerating. The issue seems to only start to get bad once the car warms up. It does not happen for the first 30 min of driving it. Happens in all gears and only while accelerating. It almost feels as if its sputtering or losing power. Maybe fuel related? Fuel pump or filter? Just looking for some advice on where to start.

Thanks

Moonshine

Start with the filter.

And stop running WOT...if it's fuel, you're going lean. Lean = baaaaad joojoo.

TRUEBLUE3934

COPS ???

kugzgt

fuel pump? clogged cats?

JeremyB

Sounds to me like it could be a sensor of some sort if it only happens when the car is warm, maybe even a coil pack starting to go out?

99roushstage2

I am experiencing this issue right now too... From around 1500 to 2200 RPM I feel a shuddering under 1/2 to WOT In each gear as if a cylinder wasn't firing hard enough. I'm pretty sure I have a bad cop. It seems to be firing sometimes and when it does it's really weak. It doesn't seem as bad under light acceleration but if I got past 1/2 throttle its really noticeable. I've swapped out all my fuel injectors and still same issue so it's not that. I doubt it's my fuel pump either bc every other cylinder is firing correctly. I'm pretty positive I have a bad cop so I it a whole new set coming in. I would maybe check yours. I tested mine with the ohm meter an they all tested out ok but I think mine is just really weak so it could have tested ok. I'm not 100% sure but this is where I've landed after tryin different things. Hope it helps.

swarthyfellow

Plugs or COP

JC316

My sisters 99 is doing the same thing. Just changed the plugs today with no change. Got coils on the way since 4 of them are still original. Hoping it fixes my issue.