jack001

Hi,
Here are some of the symptoms. I think they are closely related.
1) Elantra (2001, 90k) misfires and noticeable when the engine is started.
(Spark plug changed, not spark wires)
2) When the car runs for first mile during a day, it dies at the first few stops.
After about a mile or two run it does not die.
If i give more gas when it has died it gets of. However if more gas is not given it will not go and die again and I again need to restart.
3) Can see a reduction in fuel efficiency.
4) Can a bad fuel filter cause both these problems simulaneously?
Or there can be more issues?.

Idaho_Mechanic1984

Do you have a multi-meter to check the resistance in the wires?

If you are trying to save money then you might want to try grabbing some wires and coil/s out of a junk yard to swap in and see what happens.

A clogged fuel filter can cause this issue and I would start with that if you don't know when it was last changed...

After that I would go to the wires and coil/s...

Can you get it scanned somewhere for check engine codes?

The above 4 things I would start with (Scan for codes, Test wires and coil/s, and then test fuel pressure and replace fuel filter)

Hope this helps!

Let us know how it goes and what fixed it!

- Dale in Idaho