Engine noise through radio and high pitched squeal

[aman74]

Occasionally I can hear the engine accelerate through my radio. The TSB says this may be a resistor in the ignition coil.

Mechanic was saying the whole coild would have to be replaced, but another mechanic was saying depending on the car you can just replace the cheap resistor.

Anyone know how it is on the 01 Sentra's and have a part number?

This problem is intermittent and not nearly as bad as another high pitched squeal I get through the radio. I actually discovered something new about it last night. Normally the noise comes and goes and sometimes has some static noise attached as well. I haven't replaced the radio yet for fear that that isn't the cause. This happens with radio or cd's.

Last night the radio was doing it and I was taking in groceries with the car running. I turned off the radio and could hear a high pitched noise coming from the car somewhere. So now I'm thinking it's not the radio, but something coming through the radio that the car is doing. Wondering if it's related to the other engine revving through the radio issue.

I did find one reference to this a long time ago on the net and can't find it now.

Thanks,

Anthony

 

[Eddie]

Check the shielded antenna lead. A bad connection will do this.

 

[Quest]

engine noise (rev sound, pitched buzz, etc.) typically related to grounding shielding issues. This is particularly common if you have an aftermarket radio on it.

(if so, investigate from your aftermarket radio side first).

Don't casually throw in the "guess" of resistor in ignition coil (not), or differences between resistor plugs vs non-resistor plugs, etc. unless your vehicle has been modified beyond factory specifications (rice'ed?)

If you can hear it even with CDs, chances are, it's a grounding issue. Something is not grounded right and/or some grounding straps are broken or something. Again, this happens quite frequently if you have aftermarket radios installed improperly.

Grounding issue is also a PITA to trace.

If you can hear a high pitch squeal w/ your radio off, then it could be belt-related and you or your mech should go after the usual culprit of water pump, alternator, A/C, tensioner pulley(bearing), P/S pump, etc.

Replace the belt with fresh new ones and see if that helps.

Q.

 

[barlowc]

I had a similar issue years ago when I still had my 1998 Pontiac Grand Prix GTP Coupe. I would get a high-pitched noise coming through the speakers that would go up and down with RPMs. Part of my diagnosis included getting my alternator checked, which I removed and had done "off vehicle". It checked out fine, I reinstalled it, and then the problem was gone. My guess is that, from corrosion, a connection or ground wasn't perfect. So you might just want to check your alternator connections.

 

[tinmanSC]

I had this problem twice. Once was related to a bad ground, the other was bad spark plug wires.

 

[paulo57509]

I think this site is a little dated, but I've found it helpful in the past when I needed pin-out info.

http://www.installdr.com/

Noise related topics:

http://www.installdr.com/TechDocs.html

 

[mechtech2]

A bad capacitor on the alternator is my first guess.

 

[morris]

back in the dark ages, i used solid core plug wires, for more performance. i got interference on my radio. stoped by a 2 way radio shop. he had one resistance wire for the coil to cap. so i ended up with just one wire that had resistance. radio was fine then. however i dont think that set up can be had today.

 

[aman74]

Thanks to all who replied.

I did at one point have my horn fail on me. The mechanic who fixed it said if they had to take off the steering wheel and such it would cost a lot of money because of the work involved with the air bag, etc... He said he could re-route something with the wiring to offer me a cheaper fix.

I can't recal for sure if this problem started afterwards or not. If it did do you have any suggestions on where to look in relation to what he would have done? This would help me point my mechanic in the right direction.

Just to clarify, this is 2 seperate issues. The noise that changes with acceleration rarely happens and isn't that bad, it's a much quieter and lower tone. The TSB mentions the issue happening with FM, but I get it with AM and FM.

The high pitched squeal is very annoying and happens in all modes. I can't yet be sure it only happens when there's a noise also coming from the engine compartment as I just noticed that the other day. It often starts with a staticy noise in my rear speakers and then turns into full on high pitched pain

I have no aftermarket radio, but as I mentioned the electrical was fooled with for the horn and also a new harness the dealership put in when my car wouldn't start.

Thanks,

Anthony