I believe that my transmission may be failing… but it is just a suspicion right now based on the symptoms and my research. Perhaps someone could help solidify my suspicions?
The car is an 01 Focus ZX3. It has been laboring when getting into 3rd gear (~38-45mph?), but this USUALLY happens when going up a hill. Thankfully most of Delaware is FLAT, so it’s not always an issue. However, I’m worried that it could become more serious, since I do a lot of long distance driving. Sometimes the car “chugs” or shakes and won’t make it past 45 unless I step more on the accelerator or reach flat land. I’ve read about a solenoid in the transmission being the culprit, but when I talked to a dealership about this they act like they’ve never heard of that…
Any suggestions would certainly be appreciated. And if you have a rough idea of $$ to fix the potential problem, that would be great. Thank you.
I would be just as inclined to consider fuel filter as culprit here, before transmission. How many miles since fuel filter has been changed? At what interval should it be changed, according to the owner’s manual?
On the transmission end, have done kept up with fluid changes?
I’ve only had the car for about 9mo and driven it about 15,000mi. I don’t know when the fuel filter was changed before that, as the person does I bought it from, did not have records. 
It should be changed every 30,000mi so maybe this could be the issue… I will plan on having that done soon.
How many miles on this car? It sounds like the engine is struggling to make enough power which could be due to a lot of things; compression, fuel filter, fuel pump, injectors, air filter, spark plugs, wires, etc…
Make sure all the regular maintenance items are in good shape. Consult your owner’s manual on these. If you don’t know how long it’s been, then you should take care of those items now.
Before considering transmission, I would consider doing an appropriate 30/60/90K service on the car first. If you have a car with unknown maintenance history,any of the items Goldwing mentions below could be the issuse. It is best to start with a good, known base line and see if your car’s performance changes.
Knowing number of total miles on the car would help in focusing on possible maintenance issues first.
I’ve got to go with the others here - this sounds like engine, not transmission… and my gut says you’re not even looking at that serious of an engine problem.
The car has 115,000 mi on it. I will definitely take it in and at least get it looked at comprehensively. Do you think it would be a good idea to get a tune up? I don’t know if tune ups include very much nowadays, but I guess I could try that first.
I will definitely consider the other things first then. I am relieved to hear that it could be something much more minor. The car has 115,000 miles on it, so I’m sure it’s over-due for a tune-up. I have had the car since 100,000 miles and did not know the history other than what the owner told me (which wasn’t much).
Are these issues that can be detected by running a diagnostic on the car’s computer? (even if the check engine light is not on?) Or is it wise to just go in and request a “tune-up”?
Take a look at the owner’s manual maintenance schedule for this car. See what is recommended in the 120,000 mileage schedule.
Most likely, spark plugs, PCV valve, air and gas filter replacement is needed. That would pretty much be a “tune up”. These days, tune up is a relatively meaningless term. I prefer to be specific in what I want done to my car, rather than say “tune up” or “120K mileage service”. You may be able to do some of this work yourself, and save the harder work for the mechanic.
You may also need a timing belt replacement depending on the engine you have. There will be other recommendations (change brake fluid, change coolant, etc), but these would get you started. It would also be prudent to change the spark plug wires due to age and mileage. If you have an automatic transmission, then changing out its fluid and filter should be done. You may want to find a trusted independent mechanic to do this work since an independent is generally cheaper than a dealer on these items.
At this point, I think we are all assuming that you have no check engine light on, nor has one come on when you have had your performance issues. If not true, tell us what happened and under what circumstances.
Thank you for the advice.
The check engine light is not currently on, but it HAS been on, yes. On a recent trip through the mountains in PA, my car was struggling to get over 30mph on some hills. It felt like it was losing power fast. I had to turn the hazard lights on at one point! About 10min after driving like this the check engine light came on. It was on for about 3hr and went off. Hasn’t come on since. That was ~700mi ago.
Before that, the light has come on briefly, but this was due to other issues - one experience of overheating. That problem has since been identified and remedied so I don’t believe that is related to the current issue.
From myfocus.com Focus Forum.
Here is what should have occurred from 90K miles on, as far as maintenance. Eliminate the duplicate entries like oil change, and double filter changes, and I would get these items done, for sure. Changing plugs, filters, etc might solve your problem. These are certainly expenditures you need to do, anyway, to keep your Focus in good running shape. Next time the Check Engine Light comes on, go to a place like Advance Auto parts or Autozone, and they may read the codes (like P0000) for free. Post them here and our experts may be able to help direct you towards resolution of the check engine light. One deviation would be to get the ATF fluid changed via a pan drop and filter change (if so equipped).
90,000 Mile Service
Change engine oil and replace oil filter
Inspect brake pads/shoes/rotors/drums, brake lines & hoses, parking brake
Inspect engine cooling system and hoses
Inspect exhaust system and heat shields
Inspect steering linkage, suspension, and if equipped driveshaft and ball joints
Inspect tires for wear and rotate
Replace engine air filter
Replace fuel filter*
Replace cabin air filter, if equipped
Inspect automatic transmission fluid level, if equipped with dipstick
100,000 Mile Service
Change engine oil and replace oil filter
Inspect accessory drive belt(s)
Inspect tires for wear and rotate
Replace spark plugs
Replace the PCV
105,000 Mile Service
Change engine oil and replace oil filter
Inspect automatic transmission fluid level, if equipped with dipstick
Inspect brake pads/shoes/rotors/drums, brake lines & hoses, parking brake
Inspect engine cooling system and hoses
Inspect steering linkage, suspension, and if equipped driveshaft and ball joints
Inspect tires for wear and rotate
Replace cabin air filter, if equipped
Change yellow or green engine coolant, if equipped
120,000 Mile Service
Change engine oil and replace oil filter
Inspect brake pads/shoes/rotors/drums, brake lines & hoses, parking brake
Inspect engine cooling system and hoses
Inspect exhaust system and heat shields
Inspect steering linkage, suspension, and if equipped driveshaft and ball joints
Inspect tires for wear and rotate
Replace engine air filter
Replace fuel filter*
Replace cabin air filter, if equipped
Inspect automatic transmission fluid level, if equipped with dipstick
Replace camshaft belt on all 2.0L, 4 cylinder engines.