Avoiding ignition noise

[Heide264 10+ year member]

Got everything wired up right with a good ground and all. Problem being I keep getting a slight crackle off and on when the engine is running that speeds up when engine RPMS are up. Also very common after I back off the pedal after having it down for a bit. Assuming one of my spark plug wires are going bad.

Issue being I don't feel like replacing the spark plug wires. The van only has about 3 months of driving time left on it. Anybody have any creative/cheap ideas on how to get around it?

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[The HACKER 10+ year member]

Ummmm the spark plug wire thing is new to me....as in wtf?

Check List

1. RCA's and power on two diff sides of vehicle

2. No shitty RCA's

3. Double and triple check connections

4. Good grounds arent always good grounds

5. ground the shield our outside of rca's

6. and then theres the endless methods that you should get shortly from the friendly people of CA

 

[Heide264 10+ year member]

Going to double check the RCA grounds, but pretty sure it's ignition noise from a crack in my spark plug wires sometime. Actually swapping the eclipse I have in there with a pioneer this week (cut the head unit apart and soldered in a line to the power amp for an aux in). Just have to drill a small hole and mount a switch and do some wire measuring. Will just manually ground the RCAs with a bare wire wrapped around them before I put the hu in.

Connections are good. Not positive about the ground, but had the same issue with 2 other grounds I used. This one is on a self tapping screw right through the floor behind the driver seat. Paint was sanded off, and wire was crimped to a pretty nice lug.

No form of engine whine either. Just individual quick pops at low rpms, and almost a crackle at higher rpms. Also much worse when it is wet out.

 

[Heide264 10+ year member]

Update: Switched over my pioneer...

Did the wire wrapped RCA grounding trick just to make sure.

I drove to work in pretty heavy rain this morning... I could still hear the ignition noise, but not NEARLY as bad as it normally is in the rain. On the other hand, I only have my door amp going. The sub/amp is not hooked up yet because I am an RCA splitter short.

Any thoughts on it? I will post feedback after I get the other amp running again whether it is better or worse

 

[keep_hope_alive Premium Member]

try bypassing the ignition wiring in the car. install a relay on the car's ignition wire and power the head unit (constant and ignition) from the battery. maybe the battery can filter out that noise.

i can give you a wiring diagram later tonight if you're interested.

that's how i have my HU wired - the only vehicle wire i use is the radio ignition and it just powers a relay coil. my entire system is electrically independent of the vehicle wiring.

 

[Heide264 10+ year member]

I don't think it's the actual ignition wire, it's nose from cylinder ignition I am pretty certain. The engine in my POS astro van is right under the head unit. I think one or two of the spark plug wires has a very small crack in, and it is jumping to the car body. Hasn't gotten to the point it has effected performance, and I can't afford to fix it now regardless. The spark to the car body messes with the car body. I never thought of it being a problem with the factory wires, however.

It was back crackling just as it was during lunch. Not head unit at least.