I'm having a major problem.. First.. the car is a Hyundai Sonata .. It is a 1999 with the v6 engine. It is an automatic transmission. It has 123k miles.

The problem:

When you first crank the car.. It runs fine.. incredible, actually. After driving a minute or two the check engine light cuts on, and the car runs like its stuck in overdrive, or like really boggy. It doesn't audibly miss, but it feels like its running on 3 cylinders. Which is weird because theres no noticable vibration issue. It just feels way down on power and won't go much over 2k rpms.. even if you floor it.
It does thud hard on gear changes, so it feels like it has a broken motor mount.. but that shouldnt' cause this type of problem.


Here's sort of what I was thinking.. If the engine light comes on when it gets warm, could it be the oxygen sensors? I know that they typically don't work until they warm up.

However, the car still does it when you floor it.. shouldn't it clear up under W.O.T. as it doesn't use the oxygen sensor settings but rather a w.o.t. tune in the computer?


I may be wrong.. but any tips would be helpful. The car honestly feels like its in overdrive at 5mph even.. and you floor it and it just bogs.

Thanks,
Josh

 

First you need to have the codes pulled and see what codes are present. Let us know what codes you have. Dont throw parts on .

 

if your car is a V6, then have the CKP (crank angle sensor replaced).