What's wrong with my car?

So I have a 2002 Hyundai Elantra, automatic that has been very reliable. There’s only 1 issue. When the car hasn’t been started in a while (for instance overnight) and I start it and put it in drive, as I press the accelerator, the car stalls and moves forward slowly at idle speed. After 10-20 feet it will resume normal acceleration.



Now if I put the car in drive and keep my foot on the brake and let the engine run for 10-20 secs or so, it accelerates normally by pressing the accelerator, without the problem described in the first scenario.



Has anyone else encountered such a situation or know what’s going on?



Rob

Rob,

  1. How many miles on the car and what kind of driving do you do?
  2. Have you had the car serviced and the automatic transmission fluid checked for both correct level and if the fluid is dirty or smells burnt.
  3. If you “warm” the car up in park instead of drive does the problem go away?
  4. Is your check engine light on?

I would guess that you need to have the transmission serviced and the fluid changed. Sounds like you may have a clogged up filter/screen in the trani.
gregory (aka*.*)

Thanks for the reply!

  1. 79K on the car now. Mostly short city trips.
  2. Fluid levels have been checked and seem to be ok.
  3. Warming the car in park doesn’t seem to help. It needs to be warmed in drive to make the problem disappear.
  4. Check engine light is not on.

Thanks for the advice! Maybe it’s time for new transmission fluid.

Rob

Sounds like the fuel system is depressurizing and taking a moment to get back up to pressure again. If it were me, I’d simply wait the 20 seconds.

If that were true, then it wouldn’t matter if the transmission was in drive or park during the warm up period- but it does according to the OP.

If I’m interpreting the post correctly, the OP is describing a need to wait 10-20 seconds to normally accelerate if he/she puts the car in drive immediately after starting, if the car has been sitting for awhile. I’m interpreting the description to say that if the car is allowed to idle for 20 seconds or it has been run recently it accellerates normally.

OP, is my understanding correct?

  • mountainbike
  1. Warming the car in park doesn’t seem to help. It needs to be warmed in drive to make the problem disappear.

This seems like a key point in the diagnosis.

Yes, mountainbike, your interpretation is correct.

It must warm while shifted to drive in order to accelerate normally. After the 15-20 sec warm in drive, everything’s fine thereafter. And if I turn the car off, and come back in say 30 min, everything is normal. It seems to be only an issue again after several hours of being off.
Rob

Actually, that makes my interpretation in error. When I wrote that I hadn’t seen your second post. I didn’t make the connection to the drivetrain. Thank you for the clarification.

What is the engine doing while the car is trying to get to speed? Is it revving?

Not sure about Hyundais, but Ive read that at least some transmissions disable the fluid pump when in Park, but it runs in any other gear including neutral. Sounds like the fluid needs to get moving first. It could be a weak pump, bad drainback valve if there is one, or the fluid and filter need changing. Id start with changing the fluid and filter. If you read the owners manual I would think youre overdue for a fluid and filter change. Dont take it in for a flush. That doesnt change the filter.