Why does my 98 kia sephia idle so rough when stopped or moving slow? Also loose power going up hills

Asked by Jul 10, 2009 at 01:48 PM about the 1998 Kia Sephia

Question type: Maintenance & Repair

5 Answers


Your car may need a tuneup. You can get kits for this job, and it is not extremely difficult, but you need to pay extreme attention to every step. I wouldn't be extremely surprised at that model of car losing power going up hills simply being a symptom of a small engine.


mine does that to it might be the heat shield on the catalitic converer

it could be da gearbox 2...it happens 2 me nw......


The tps, throttle position sensor may not be working. This would lead to rough idle, and some loss of power, but it could also be a misfire in one of the cylinders. Check plugs, leads, etc. Ask yourself does the car need a service, when was it last done? It would be best if you could get a read out of any fault codes that may be stored in the ecu first, find a garage that will use a code reader to do this, cheaply mind, or get one for yourself. There are many other issues that can be involved, but check the cheapest first, plugs leads etc. Tps sensor is a best bet for rough idle on tick over, and during a journey.

1 of 1 people found this helpful.

A tune-up may be necessary. I suggest "Boche" platimum sparkplugs. The job may look intimidating at firtst, but careful accounting of the bolts and other parts be a must.

1 of 1 people found this helpful.

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