2002 Ford ZX2 long-standing mystery problem (wall of text)

ford
zx2

#1

After trying my luck over the years with multiple mechanics, I thought I’d see what ideas the folks in this forum have. I drive a 2002 Ford Escort ZX2, 135K miles on it right now. For EIGHT YEARS, I’ve had trouble with the transition between first and second gear (it’s an automatic). When I begin to accelerate, the car sort of gets stuck/hesitates and then jumps into 2nd. It’s not a huge lurch but it’s definitely noticeable, as if I were really bad at driving stick. It has this ‘gap’ between gears both on acceleration and on deceleration. Unsurprisingly, it means the car is unpleasant to drive in situations like stop and go traffic, or parking garages – times when you’re driving at a low speed, at the higher end of 1st.

It happens intermittently, though more often than not. It doesn’t seem to be affected by weather or by warming the car up/running it cold. I should also mention that very seldomly (a couple times a year, maybe), the car gets stuck like normal but DOESN’T shift into second, so it’s almost like I’m suddenly in neutral. I can sort of ‘wake it up’ by switching into a lower drive gear and then switching back. If I leave it in drive and just hold steady on the gas pedal, it also will eventually kick itself into the next gear.

It first started happening about a week after a long road trip (New York to Oregon, where I now live). I took it first to a dealership (at the time it was still under warranty) and they couldn’t find anything wrong with it. A few months later I took it to another mechanic, who couldn’t replicate the problem in a test drive and so also couldn’t find anything wrong with it. And that’s pretty much been the story. At this point at least five mechanics have looked at it and nobody can pinpoint anything.

Now I also have a squealing noise, which I assumed was a belt. When I went to have it looked at by my mechanic, they puzzled over it for awhile and finally told me it was the VCT solenoid, only they called it something different (they are a european car mechanic and see very few of my model car, but they’re very honest and I love them). I only narrowed it down to VCT solemoid by calling a family friend who’s a Ford mechanic. So I took it to the dealership to have the VCT solenoid repaired, but they told me there was nothing wrong with the car. The noise goes away once the car is warmed up.

In case it’s of any consequence, in the past few years I’ve had the timing belt done (and serpentine belt and water pump along with it, since they were removed at the time anyway), and then just recently had to have a serpentine belt pulley replaced. Other than routine maintenance and a teeny number of one-offs, the car has been really reliable. It has the signature rough idle of its make and model but I just try to tell myself I’m getting a nice butt massage.

I am planning to make another cross-country drive in the next few months and I’m trying to be as sure as I can that I’ve repaired everything that needs fixing before I leave. Any ideas would be most appreciated. I don’t know how to do any work to it myself so I’ll have to direct my mechanic (now someone other than the european car place). Thanks in advance!


#2

This is the entry by @bent_rod. He includes photos and apparently this is a very common problem.

"The old design pressure regulator spool valve would sometimes get stuck by junk floating around in the fluid. When it sticks the transmission will have very low line pressure, causing it to slip or not work at all. This is the place I got the valve kit from: http://www.transmissionpartsusa.com/F4A … 033933.htm

On my 2000SE it would slip (race engine) between shifts when the fluid was very hot. That was with the new pressure spool valve and spring kit. As I posted above in this thread I installed the electrical mod that raised the line pressure, now it does not slip. Ford F4A-III automatic transaxle EPC pressure riser http://mechdb.com/index.php/Ford_F4A-II … sure_riser

Edit to show photos of spool valves and springs."
Old parts on left, new on right side of photos.


#3

Oh wow – thanks so much! Somehow I’ve never run across mention of this particular fix. This is all extremely helpful info!