Ignition interference in the radio

[DMC-81]

Hello,

I'm getting some ignition noise through the radio. So, what part(s) are there to suppress this ignition noise / interference on the DeLorean? Is it Coil suppressor, part number 108561? I see in THIS (https://dmctalk.org/showthread.php?17579-Suppressor-coil-108561-importance-function) thread it may not be, but if not, what part is it?

Also, I use my cigarette lighter to power an audio device. Is it necessary to add suppression to this power circuit as well, or is the OE radio suppression supposed to cover all power circuits in the car?

I know from working on other old cars there is a capacitor in the ignition system, and these capacitors wear out over time and have to be replaced.

Thanks for your input.

[David T]

Before you think about suppression, check the ignition system. Maybe it is time for a new set of wires, cap, and rotor. Maybe you have the wrong plugs. The caps are mainly for suppression of snapping noises like when you turn switches on and off and the alternator, not ignition noises. It can also be a bad connection on the antennae, weak radio signals, a problem with the radio, etc.

[Bitsyncmaster]

A lot or radio noise is corrected by running a new radio ground wire so it does not share the ground with other electronics. Run it from the ground feed through behind the relay compartment.

[DMC-81]

Before you think about suppression, check the ignition system. Maybe it is time for a new set of wires, cap, and rotor. Maybe you have the wrong plugs. The caps are mainly for suppression of snapping noises like when you turn switches on and off and the alternator, not ignition noises. It can also be a bad connection on the antennae, weak radio signals, a problem with the radio, etc.

Thanks for your input. BTW, the ignition system is new and OE, and I have the correct Bosch silver spark plugs.

[DMC-81]

A lot or radio noise is corrected by running a new radio ground wire so it does not share the ground with other electronics. Run it from the ground feed through behind the relay compartment.

Thanks Dave. I'll check the ground and I may run a dedicated one as you suggest.

[DavidProehl]

Are you getting noise on the radio itself when listening to an FM station or aux input? I had a situation with my aux input on my Craig headunit due to the poor grounding. Running a new ground as Dave suggested is certainly the best option, but I found I was able to get by with a ground loop isolator. No question it is treating the symptom rather than the problem, but it gets the job done well enough for my needs.

I use one similar to this: https://www.amazon.com/BESIGN-Ground-Isolator-Stereo-System/dp/B06XQYN77L/

[DMC-81]

Are you getting noise on the radio itself when listening to an FM station or aux input? I had a situation with my aux input on my Craig headunit due to the poor grounding. Running a new ground as Dave suggested is certainly the best option, but I found I was able to get by with a ground loop isolator. No question it is treating the symptom rather than the problem, but it gets the job done well enough for my needs.

I use one similar to this: https://www.amazon.com/BESIGN-Ground-Isolator-Stereo-System/dp/B06XQYN77L/

Yes, I mostly use the aux jack, but there is some noise there using the radio. Thanks for the link to the product. I'll definitely try that!