QuestionQUESTION: hi HT
I recently have a problem with my elantra 2006,
when my engine is still cold, or just started up, my engine give a wrangling sound between 1500 to 2000 RPM, but the rest of the rev range is good and normal, both below and above these values it give a wrangling sound like a vibrating part of the engine compartment is causing it , but i have inspected and investigated the engine compartment, it seem that there are no part that may vibrate
in addition, this problem is gone when the engine has warmed up.
but some times, this problem does not manifest it self at all. it is therefore intermittent but that is occasional, only and very rare.
The acceleration has no problem as well as the idling, I do not know if there is a MIL light, cause in some instances when I removed a connector on the MAP or alternator the car does not give me an MIL warning.
Thank you and
best regards.
ANSWER: Sometimes noises that occur at a particular RPM are caused by loose exhaust shields or other vibrating components. Usually, the easiest way to detect is to operate the throttle under the hood and look and listen for the vibrating component while the noise is occurring.
The easiest way to check if you have a malfunction indicator lamp (MIL) is to turn the ignition key to the on position (without starting the engine). If you have a MIL, it should illuminate when the key is in that position. If it doesn't, you either don't have one or the bulb is burned out or missing.
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QUESTION: Thank you very much HT,
Just a follow up,
I have inspected all possible part that could vibrate under the hood, and my exhaust rubber suspensions as well, what really gets my curiosity is that it only happens at RPM's 1500 and just before 2000, I tried manually turning the throttle to settle the RPM at 1500 (parked and wheel blocked), but the throttle idle, keep pushing it upward and when it reached above 2000, the vibration ceases,but just, in between those two RPM's just before going above 2000 the vibration is evident.
I cannot seem to manually (without load to the engine) settle the engine at 1500 to 2000, but under load when the car is running on the road, I can settle it between 1500 and 2000 and the vibration is very evident, and above 2000 it just purr like a kitty, acceleration is not affected under any RPM
It sounds like a Grrrrrrrrr, just before it hits above 2000 and then quiets out and the engine just purrs.
I just could not understand what causes it, I read and searched the Internet, but nothing describes the same problem that I have.
thank you very for your time.
and more power to you.
Cezar.
AnswerI was referring earlier to the heat shields on the exhaust pipes, not the hangers. Sometimes a small portion breaks free and allows the shield to vibrate at resonant frequencies.
You may need to have an assistant rev the engine while it is in gear. This will enable you to search for the noise while the engine is revved under load.
And lastly, it's normal for this engine to make a noise similar to what you describe, especially noticeable when the engine is cold. Of course, if this is the noise, it would have existed over the life of the car and wouldn't be new just now.
