Transmission jerking only at high RPMs after long distances

ford
focus

#1

I have a 2002 Ford Focus ZX5 with about 108,000 miles on it. It’s driven far distances, about 700 miles round trip, a couple times a month. About about three times since last summer, approximately halfway through one leg (at around 200 miles in), the engine starts jerking when accelerating. It doesn’t happen on every trip, and seems to only happen on hotter days. (Driving around town short distances, even at high RPMs doesn’t present a problem at all, it’s specifically after a couple hundred miles.) The engine light has flashed, but not every time the jerking occurs and hasn’t stayed on, and the code that was pulled doesn’t seem to be helping either the mechanics or Ford know what the deal is. I’m looking at having the whole transmission swapped for well over a grand, but with the disclaimer that it’s not a guaranteed fix. Has anyone heard of this problem before that might be able to save me time and money?

Thanks in advance to anyone who can help!


#2

Why are you so sure it is the transmission jerking? It could be the motor missing. Does the car have traction control, if yes it could be the traction control killing the motor for an instant. It might be a CV joint going bad. Too many other possibles to spend a bunch of money with no guarantee another transmission will fix the problem.

Try some Ford Focus forums and see if you find something similar to your problem. It sounds like what my T’bird did when several of the COP’s (coil on plugs) were going bad. Heat causes electircal stuff to go funky sometimes and I think you have a heat related problem that has nothing to do with the transmission.


#3

“the code that was pulled doesn’t seem to be helping either the mechanics or Ford know what the deal is”

What was the code?? Inquiring minds want to know!


#4

+1 to what Uncle Turbo mentioned.
I agree that the problem you are experiencing is just as likely–if not more likely–to be an engine-related driveability problem, as compared with a transmission problem. Make sure that all possible engine issues have been dealt with before you go to the expense of transmission repairs.


#5

Thanks for the advice.

I called for the code, P1780? It was pulled by some shop I stopped outside of Indianapolis, but then when I got home to Chicago the mechanic there says the code the dude from Indy put in there is indicating that it’s a transmission control switch but that the mechanic and his Ford guy haven’t ever heard of this. He either wants to replace some valve or swap transmissions.

I will, continue to search for solutions I suppose. Thanks!


#6

That code is indeed for a “transmission control switch out of range”, but the problem could just be related to wiring problems, or there could be a need to replace that switch. This should not be a situation mandating replacing the transmission unless there are other transmission issues–or if the person making the diagnosis needs to make the latest payment on his boat.

Bear in mind that the electronic controllers for both the transmission and the engine do need to “talk” to each other constantly, so there is also the possibility that the engine is misfiring under load because of bad communication with the transmission control module, as a result of a wiring problem or a bad trans control switch.

Another possibility is that a problem with this switch or its wiring may be preventing the transmission from shifting properly into and out of overdrive. Overdrive-related problems can sometimes feel like “jerking”.


#7

Just as an update, I drove the car from Chicago to Columbus, but took the back roads rather than the interstate. No jerking and the mileage was a lot better than it was when I was going 70/75 on the interstate over the last few weeks. I took it into my regular guys anyway with the paperwork I had gotten when I pulled over in Indy. They said they drove it about 40-45 miles and that it’s running fine, they can’t find any issues with it, and that the crazy guy who wanted to swap the transmissions cleared the code out of the engine so there’s nothing else they can do.

I guess it’s better than having dropped $1300 on a new trans, but it’s still kind of weird no one can figure out what’s wrong with it. If it ever gets resolved, I’ll definitely be letting you guys know, this is kind of ridiculous… Thanks for the advice though!


#8

Change your Crank & O2 Sensor


#9

sgrprit1987 you are about 4 years too late.


#10

I am not good at it