How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Greg Your Own Question
Greg, import technician
Category: Hyundai
Satisfied Customers: 7088
Experience:  27 year and 16 year as shop owner, import technician
Type Your Hyundai Question Here...
Greg is online now
A new question is answered every 9 seconds

Hyundai Tiburon: 2001 that has a idle problem

Resolved Question:

I have a 2001 Tiburon that has a problem with the idle. After driving the car for awhile, and it is warmed up and then I come to a stoplight  the idle should slow way down in a very short time , but it does not. It takes 5 or 6 seconds to slow down to normal, and sometimes, it will run high then low, run high than low, it will do that several times also. Its irratic. I think it is wasting a lot of gas doing this. I have already replaced the throttle control sensor, didn't help. Can you? thanks
Submitted: 5 years ago.
Category: Hyundai
Expert:  Walt-Mod replied 5 years ago.



I'm a moderator for this topic and I wonder whether you're still waiting for an answer. If you are, please let me know and I will do my best to find an Professional to assist you right away. If not, feel free to let me know and I will cancel this question for you. Thank you!

Customer: replied 5 years ago.
Yes, I am still waiting for an answer. Must be a tough one for ya?! I am waiting for an expert. Thanks
Expert:  Walt-Mod replied 5 years ago.
Sometimes, finding the right Professional can take a little longer than expected and we thank you greatly for your understanding. We'll be in touch again shortly.
Expert:  Greg replied 5 years ago.
Name is XXXXX XXXXX i will assist you the best i can, please Only accept if you are happy with my answer.

Is your check engine light ON when the engine is running .
was the system checked for codes.
throttle control sensor did you mean the IAC (idle control valve)

Customer: replied 5 years ago.
TAP-Throttle position sensor was what I replaced. Sorry mis-stated. And no, the check engine light is not on at all.
Expert:  Greg replied 5 years ago.
Hi .

I suggest you check the throttle body for carbon deposits and the
idle control system .

IDLE SPEED CONTROL (ISC) Actuator the idle speed control actuator is the double coil type and has two coils. The two coils are driven by separate driver stages in the ECM. Depending on the pulse duty factor, the equilibrium of the magnetic forces of the two coils will result in different angles of the motor. In parallel to the throttle valve, a bypass hose line is arranged, where the idle speed actuator is inserted in.

The IAC may just need cleaning , when this malfunctions it will set a code but if no codes then just may need cleaning ,

Check for vacuum leaks bad vacuum hose connections or miss routed ,

Hope you did not use Bosch spark plugs as theses will give you problems .

No code idle problem is normally a dirty throttle body ,IAC dirty ,miss routed vacuum hose or damaged ,vacuum leaks .

Need further assistance with this issue please get back to me.

Customer: replied 5 years ago.
What is the IAC? Is it different from the ICS?
Expert:  Greg replied 5 years ago.
Hi sorry these are one and the same , as shown in the diagram above
and here below.

Kind regards Greg
Customer: replied 5 years ago.
I am a pretty mechanical type guy. But, on a scale of 1-10 , ten being the hardest, How would you rate , "the removal, clean , and reinstall the unit" ? .
thanks for your help
Expert:  Greg replied 5 years ago.

I would rate the ISC a 1 and the throttle body a 3 .
for mechanical minded man

Regards Greg
Greg, import technician
Category: Hyundai
Satisfied Customers: 7088
Experience: 27 year and 16 year as shop owner, import technician
Greg and other Hyundai Specialists are ready to help you
Customer: replied 5 years ago.
Sounds encouraging. I will try it. I'll just use some carb cleaner or something any suggestions?
I recently bought the car, and it had been sitting for 9mos. apparently, it was a little banged up. I also put fuel injector cleaner in awhile back, no help on that.
Thanks again for your help.
Expert:  Greg replied 5 years ago.

Carb cleaner will work just right ,

clean the throttle body flap on both sides use an old tooth brush to clean. after cleaning leave the flap open and wait for the carb cleaner to evaporates then start and try

do the same with the ISC remove and spay clean if dirty .



Customer: replied 5 years ago.
I cleaned it today with brake cleaner. I used little brushes and shop paper towels , thought I got it pretty good. I drove to the store 15 minute there it seemed fine. Was only in the store ten minutes, drove home and just as I pulled in the driveway slowing way down, the idle starting acting irractically again, high idle then low, high..low. Up down. So, it is still not fixed. And yes the sparks plugs are bosch. I know , change the plugs, but I don't think will be that easy....but maybe I'm wrong...The thing I cleaned was silver the ICS I believe.The electrical harness connection looked great. Any other suggestions? Thanks, Brian
Customer: replied 5 years ago.
what is the throttle body? and do you have a diagram of vaccum connections? Thanks.
Expert:  Greg replied 5 years ago.