I have a 2003 Ford Focus SE, manual transmission, and a couple days ago when I started it, it seemed to be acting a bit weird. When accelerating, the car would stutter and choke like it wasn't getting the right amount of fuel. It gave me symptoms the car had given a few years ago, when the spark plug wires had gone bad.

I couldn't accelerate barely and when I did, it responded like I was flooring it. A sudden jolt of energy before shifting and running into the same issue again. Once I got it (towed) home, I changed the fuel filter.

After that didn't work (though it certainly sounded a bit better), I changed the spark plugs and wires to eliminate potential causes. One one of the wires, the plug connecting to the ignition coil/distributor (I'm not 100% sure what it's called) had a chunk of corrosion on it.

The change made a significant difference, but when I was going 70 down the interstate, cruise control engaged, I started having issues again. Engine light was flashing, and when I went to step on the gas, the pedal was completely pressed down by cruise control.

It passed after a bit and I was able to make it to my destination. However taking off from a stop, there's the same sputtering and hesitation as before with jerks and the like as if the car is trying to go but barely can. After a bit, however, it starts driving again normally.

Idle is a bit rough. I can hear distinctive clicks inside my car that sound like those from the fuel injectors.

I feel it could be something with the fuel system, but given the massive change after replacing the spark plugs and wires, it feels like it could be something electronic.

I'm open to ideas. Gonna try the OBD scanner, but if the check engine light isn't on I'm not sure what it'll tell me. I have videos of what it sounds like when I try to accelerate if that'd help at all.

Thanks for any advice you can offer.

Comments (11)
No. 1-4
Lunar Firefly
Lunar Firefly

@Techsus @dirty dan @ScottyKilmer @ernestoc33 Thanks for all the help. I ended up going with my gut on this and decided to try replacing one more part before having a mechanic look at it.

It occurred to me that a few years ago when I replaced the spark plug wires, that the symptoms I had been having then were extremely similar to what I described in the original post. The corrosion on the wire was also bothering me, so I picked up an ignition coil from Napa, and replaced it. I discovered one of the plugs on the ignition coil looked burned, and gross when I pulled it out. The rest looked fine, but that one was in bad shape and I think it was the original. The difference was massive with the replacement. It completely fixed the jerking, hesitation, and rough idle.

Honestly it's running better than when I bought it.

Thank you again for all your suggestions!


Paying a diagnostic fee might be cheaper than throwing parts at it. The shop I go to charges $60 flat so it's not crazy expensive and they apply to the invoice if they do the work.

Scotty Kilmer
Scotty Kilmer


have a pro pressure test it with his special gauge and fittings

dirty dan
dirty dan

Try checking the fuel pump and fuel filter often time a clogged filter or worn pump can cause stuttering