I've got a 2001 Accent GS, and it's having 3 problems.
1) Cold Start - On a cold start, the engine will chug / putter until i give
it some gas to rev the engine, then all is good. If i don't give it any gas,
it'll stall out. Once it's been started once, this problem is gone.
2) Shifting - When comming to a stop, the trans. will quickly shift up, then
down, for each gear as i slow down. Once i'm at a stop, the idle is
slightly higher (about 1100rpm instead of 800-900)
3) Idling - When the car is in neutral, the idle is higher then normal, but
varies. Again, if i give it some gas, and bring the rpm above 3k and let it
drop back down, it will go back to idling fine.
Now here's the weird part. All 3 of these things are completely intermittent.
They all happen at the same time, but the car can go days with no problems,
and some days, it does it all the time. Generally, all symptoms are present,
or all are gone. No middle ground.
I took it into a service center, they couldn't find anything. They said O2
was fine, fuel in and out was OK.
No fault codes where present. They couldn't explain the shifting problem.
This problem started all of a sudden. We has similar problems when we first
got it (shifting issues), and the O2 sensor was replaced at the dealer, and
it was Ok after that.
I'm lost for what this could be.