rev below 800rpm

[CMF_siblinghk]

could anyone tell me what the problem is as my micra(98) rev below 800rpm to 600 rpm when the engine starts , it also rev unstablely in between 800 and 600 rpm when the car is stopped. i suspected exhuast problem, but the garge people told me there is nothing wrong with it.. i bought the car for just a week, and it has been modified by previous owner: induction kit and lowered. i dont know much about car so anyone knows what the problem is and how to fix it, please tell me.... thanks in advance....

 

[CMF_Yom]

Check for air leaks around the induction kit.

 

[CMF_lam.666]

http://micra.com.au/technical-articles/cg13de-throttle-body-resoldering-guide.php

 

[CMF_siblinghk]

Yom WROTE:

"Check for air leaks around the induction kit.

if the problem persists, will it damage the car or engine? many thanks

 

[CMF_Yom]

If there is an air leak there is the potential for debris like dust and sand to enter the engine. This will cause premature wear and tear meaning the engine won't last as long as it would if the air was being fitlered properly.

 

[CMF_siblinghk]

i have checked and adjusted the industion kit several times, but the rev's still unstable, whatismore, when i drive for 15 mins, i heard some sound like whistle underneath. please someone tell me how do locate the leak or hole, as it makes me worry that the engine is always overheated.