I have a 2003 hyundai elantra vibration problem

Here is the fuse box diagram, but the Elantra appears to have a rather funky battery fuse! Most vehicles have a main battery fuse but it is on the battery connector wire. If you put in a new ECM, was it programmed to the vehicle?

https://www.autozone.com/batteries-starting-and-charging/battery-fuse/hyundai/elantra-gt

Hyundai Elantra (XD; 2000-2006) fuses and relays

Fuse Box Diagrams https://fuse-box.info > hyundai > hyundai-elantra-xd-...

The fuse box is located on the driver's side of the instrument panel behind the cover. The location of the fuses in the passenger compartment: Hyundai Elantra ( ...

Remove one of the spark plugs and check to see if it is getting spark. If it is not getting spark then you have a ignition problem.

Replace left front fender - Fixya

www.fixya.com/cars/t26028082-replace_left_front_fender

Dec 29, 2015 - replace left front fender - Hyundai Motor 2003 Elantra question. ...Question about Hyundai Motor 2003 Elantra. Open Question ... How do i remove left front fender clip on a Lincoln ls 2002? Jan 04, 2015 ' 2002 Lincoln LS.

Replace 2003 hyundai elantra front passenger outside door ...

www.fixya.com/cars/t17348691-replace_2003_hyundai_elantra_front

Mar 26, 2013 - Question about Hyundai Motor 2003 Elantra. Open Question.Replace 2003 hyundai elantra front passenger outside door handle. Need to replacebroken exterior door handle on front passenger .... replace left front fender.

Have your idling speed adjusted. If it will not help, try replacing the air cleaner. If it will not solve the problem, then there are several checks to be done.
Check if the pump is delivering the right amount of fuel. Check if there are intake manifold leaks. Check if head gasket is leaking, Check if ignition timing is right. Check if valve clearance is out of adjustment. Check for worn out timing belt. Check for worn out cam lobes. check for clogged injectors.

check for a weak or broken engine mount. most likely the one on the right side of the engine has gone bad.

The vehicle speed sensor is probably faulty. Have it checked. it's mounted on the side of the tranny.

Take/Tow your vehicle to an authorized Hyundai dealership and pay the diagnostic fee... they will tell you exactly what the problem is and the cost of parts/labor to fix it... at least this way you'll know what the problem is and what's required to fix it.

could be timing belt, but most likely is going to need spark plugs, plug wires, and maybe ignition coil.

contact ehyundai with the V.I.N and they should be able to help you.. i am presuming it is for the stereo.

Very wild guess. I replaced the bearings in my 2003, and was looking in my tool box. I came across a 1 1/4" socket that I purchased around the same time, but I realize that it should be the metric equivalent of this, so it probably did not fit perfectly. Metric conversion would be 31.75 mm.