Need help with 2000 Kia Sportage performance problems

Hey all,

I have a 2000 Kia Sportage and I am having big time problems with the car. The check engine light is on and it is running so poorly that at the moment I am having problems getting it started and if I do get it started I am lucky to get enough power to get up to 2nd gear and higher.

The car failed the New Mexico emissions test earlier this year and I have talked to the dealer and others regarding the problem. Initially the problem started as hesitation, as oftentimes while driving at a speed of like 55 I would notice a reduction in power and my speed would drop down to speeds like 35 and lower for awhile.

I have read the codes in the car and at this point in time I am getting the following codes:

1. P0301, Cylinder 1 misfire detected.

2. P0300, Random/Multiple cylinder misfire detected.

3. P0304, cylinder 4 misfire detected.

4. P0302, Cylinder 2 misfire detected.

So far the spark plugs, ignition coils & wires have been replaced, the O2 sensor has been replaced, one catalytic convertor has been replaced, and the exhaust manifold has been replaced.

The fuel filter has also been replaced and the fuel pump has supposedly been testted and passed. It has been suggested by some that it could be the catalytic convertor while others have said that it could be the fuel injectors or the timing.

This problem has been getting steadily worse over time. I have even replaced the gas cap. After I replaced the plugs and the gas cap it passed the emissions test as at that time I was only getting the cylinder 1 misfire. After passing the emmissions test and thinking that I had licked the problem I treated myself to Baskin Robbins. When I left the car started stalling and hesitating and due to the stalling and hesitating I replaced the coils thinking that was the problem.

It helped for a little while, but then the problem resurficed. It was later discovered that one of the coil wires was bad and that was replaced and I was told that the catalytic convertor was plugged and needed to be replaced. They told me that it was welded on and that they could not do it.

I took it to another shop that did a blowback test at that convertor to see if that was plugged and it passed that test, but the mechanic there stated that supposedly this car has two catalytic convertors on it and that it is possible that the catalytic convertor that is by the exhaust manifold could be plugged and that it was a special order part.

Does anyone have any ideas as to what could really be causing these problems? I am wondering as I am needing to get this car fixed right away and I am trying to figure out what is actually causing the problems and as to how much it might cost me to fix this problem.

If anyone has any ideas about this, then I would greatly appreciate it, as this problem is starting to get very confusing and stressing. Any ideas or suggestions would help. I am trying to find the culprit of the problem and fix it soon and hopefully as inexpensively as I can.


You may find some leads at: Click on Tech Notes. A good scan tool and/or a good shop (ask around) could be the best way to go. Go to the bottom of this page and click on Actual Car Info. On the next page, scroll down to Mechanic’s Files, input you zip code, and the mileage radius you’re willing to go to a shop listed. There will be customers’ comments about the shop. Call and talk.

Several things it could be. Offhand, I might be leaning toward the crank sensor primarily.

A leaking fuel pressure regulator or clogged converter could cause these problems but the symptoms should not be a come and go situation like you have. A converter can become clogged due to a poor running engine.
Both of those items are easily checked though.