So my car (1996, Mitsubishi Gallant) was running fine when I took it in for a long overdue oil change on Friday.
I pick it up from the mechanic and immediately I start having problems.
The car would often shudder and shake when coming to a stop and the rpms would fluctuate and one time even caused the car to die. I took it back to the mechanic that night and they took a look under the hood. The dipstick wasn’t in all the way they said and that can cause the car to behave oddly. So I took the car back out and it seemed fine the rest of the drive home. I didn’t have to drive the car again until Sunday, where immedaitely the same problem occured only it got worse. Driving to work today the car has now begun to shift gears (it’s an automatic) very hard.
I’ve also noticed that putting the car in reverse makes it shudder and vibrate loudly on the right side.
Now before I take it back to the mechanic tomorrow…does anyone have any idea what is actually wrong and how they might have f-ed up my car?
My brother once emptied the transmission fluid of my dad’s car and then put in 5 quarts of oil.
So the car was then running without transmission fluid and with double the amount of oil it was supposed to have.
Anyway, I’d check the transmission fluid level.
Okay, first of all, I’ve never heard leaving out the dipstick causing any kind of short term engine misbehavior. You don’t want to leave it out long term because of contamination, but you’re not going to kick a significant amount of oil back up the dipstick tube. That’s just specious nonsense.
As for your problems, if you’ve checked and made sure that the oil sump is filled to the correct level (check while the engine is cold or has had about 30 minutes or so for the oil to drain from the engine and into the sump) then it may be that they used the wrong weight of motor oil in the car and you aren’t getting effective lubrication until it warms up. It’s also possible, since you say the change was “long overdue” that the sludge in the old oil was masking some signficant bearing wear problems, but I wouldn’t expect this dramatic of a difference from an oil change.
The transmission issue is a little worrying, though; as a wild guess, it sounds like someone either drained fluid from the transmission case and/or added the wrong kind of fluid. This is easy to do by accident if you’re a complete idiot, which I’m sorry to say many employees of oil quick change establishments are. Take a look at the tranny fluid and see if there is any “marbling” of fluids in there; if so, get it all flushed promptly. Actually, If you want to be on the safe side, take it to another (real) mechanic and tell him about your issues; he’ll probably be able to give you a better opinion as to whether the problems are hidden legacy or newly caused.
Some engines are very sensitive to the amount of airflow through the PCV system. It’s not uncommon for a loose or missing dipstick or oil cap to affect the idle.
That would plausibly explain the first symptom described, especially considering the symptom ceased when the dipstick was properly seated.
I have doubts that the further symptoms are related to the above, both because of the nature of those symptoms and the delay in their onset. Something that happens in only one gear suggests a problem in the transmission, not in the engine. (A possible exception is a worn or broken engine mount, which is pretty hard for someone to cause.) Nothing readily pops into mind that would explain the three symptoms mentioned.
I agree that this can occur from a loose or missing oil filler cap, but I’ve never encountered a wet sump engine so affected by a missing dipstick. I suppose air flow could be an issue with a dry sump system sucking air into the oil channel, but I’d expect a passenger car engine to be fairly tolerant of this. I’ll freely admit that I could be wrong, though; it’s just outside of my experience.
A loose cap is more common, and has more effect, than a loose dipstick. In many cars the dipstick air leak wouldn’t be noticeable, but I have seen it in some.
Is the engine light coming on now?
I wonder if they disconnected an emmission control device (some type of electrical sensor) either by accident or to get to something they needed to replace.
Did they replace the air filter?
IOW, what other work was done?
Check under the hood for some electrical connection that may be unconnected or a vacuum hose that’s loose or off. The rough idle and hard shifting could be a vacuum leak.