Recently I noticed a buzzing sound (noise) coming from the engine compartment when the car runs under load, e.g. when on an uphill and want to accelerate, taking off from a stop, etc. The noise goes away once I am cruising on lower RPMs but it always comes back when you step on it. The power is still there but the noise is annoying. It almost sounds as a slightly loose heat shield, but all exhaust parts are in place. I've changed the PCV valve (though I did not notice any variation in idle RPM prior to this), I put in new NGK Iridium plugs, car has only 60K on it and is 2K. It has the original old coils. Now, I am wondering, would a bad or a going bad ignition coil cause noise like this and can the coils be tested for functionality and how if so? Thanks...

 

ignition coils go bad with the engine light on, a code reading "cylinder * misfire" (p030*)or "multiple misfire" (p0300) or "bad ignition coil" (p1320) accompanied with severly reduced power, possible stalling and or 'engine shakes'

peace

 

^^that is incorrect. not always does a bad coil throw a code. this has been discussed many times.

 

is there any loss in power? ususally if the coils are bad and the plugs are changed, it will throw a code. it does not sound like the coils are bad. when did you change the a/c and alternator belts?? when you floor it, what happens?? does it "GET IT" or do you experience hesitation?

 

There are no codes set. The power is always there, no hesitation.

Hm, belts are a good idea! I think they are original. I'll change them both and see what happens...

Thanks for the suggestion and education on coils!

 

Another thought, sometimes the car does not start on the first key turn, it almost feels like it is starved. Then when I turn the key for the second time, with a small struggle, it does fire up. This happens at random, perhaps once a week. No particular pattern with regards to engine temperature... Would this be a related problem? I got the belts and will change them tomorrow...

 

I have this exact same problem

 

Anybody know how to fix the coils yourself?

 

You don't fix the coils - you would have to replace it altogether. Sucks when it costs $80.

 

NOOOOOOOO

Please no...i really don't want to replace my ignition coils!
somtimes when i start my car up it sounds like a WRX with exhaust...

 

As far as the topic at hand: It's normal. Pefectly normal, in fact. If you have your Owner's Manual look at section 10, page 4.

 

coils aren't hard to replace, it tells you how to remove them in your owners manual under removing or replacing spark plugs

 

it took me 5 minutes for one bad coil, theyre just expensive, go to classifieds 5 gen forum and look for the thread on $235-$260 shipped for all six

 

"As far as the topic at hand: It's normal. Pefectly normal, in fact. If you have your Owner's Manual look at section 10, page 4."

Thanks Arnold. That's a valid point, however, I am running 94 octane gas in my car. Here is what I found: The starting problem went away after I cleaned the throttle body. I have not had a bad start for more than a month now. For the noise issue, I put in new NGK Iridium plugs, and replaced both belts and the noise was still there. Then I raised the car and checked all exhaust heat shields and found that one just before cat was slightly loose. A $1 clamp tightened it and guess what - the noise is gone. Thank you all for your contributions and have fun :-)

 

Ahhh the infamous heatshield rattle. Its been a while since I heard that one come up.

Glad you found it!

 

i have a similar thread in this forum but NO ONES RESPONDING!!! i just went to autozone..my car was shaking on an incident last week with the slip and tcs light on but recently no codes been thrown and no shaking/weird acceleration.

couple codes came up after teh comp was plugged in...P1320..and P0301-cylinder 1 misfire. p0740 - circuit malfunction also but that might be because of the 5 speed swap on the car...a whole lotta 5 speed swap related solenoid problems came up lol..

supposedly the 1320 and 0301 are both related to the ignition coils...but should i replace the one or all 6?? last three days when ive been starting the car, theres a noise coming outta the engine...it takes like half a second more to start and u hear like a zippp.. like what you hear when you turn the ignition when the cars already on!!! maybe cause of the faulty coil?? please help... need answers!!!

 

I have the same problem also as the first guy. I did recently change my Y-pipe. I do have a SES light and had it pulled. It said it was a misfire but didn't pinpoint it. I changed the plugs reset the ECU and I still feel a random misfire and SES light. I'm going to try and get the code pulled again. I have a feeling it's my coils. I do notice a rattling sound when I punch it. But I swapped the Y-pipe and there aren't any more heat shields except over the cat.