AARRGH! Radio cuts out since installing HEI

[StoningtonQB]

I've been having a problem with my radio ever since I converted to a GM HEI distributor. The radio will cut in and out. When the truck is off, I can turn the key to ACC and it works fine. The green wire for the tach runs thru the firewall but it's a good distance from the radio. I've tied up all of the radio leads and have experimented with some temporary sheets of aluminum foil to separate the tach lead. Everything is decently far, at least 6+ inches, and it doesn't look like re-routing this wire is going to change things.

Nothing seems to be working. The foil was just a test and I'm probably going to take that stuff out of there. I'm running cut-to-fit MSD StreetFire wires which claim "high EMI suppression" so I don't think that's the problem. Is there a way I can shield the head unit somehow from all interference? It's a RetroSound Hermosa if that makes any difference.

[BrianG]

Originally Posted by StoningtonQB

I've been having a problem with my radio ever since I converted to a GM HEI distributor. The radio will cut in and out. When the truck is off, I can turn the key to ACC and it works fine. The green wire for the tach runs thru the firewall but it's a good distance from the radio. I've tied up all of the radio leads and have experimented with some temporary sheets of aluminum foil to separate the tach lead. Everything is decently far, at least 6+ inches, and it doesn't look like re-routing this wire is going to change things.

Nothing seems to be working. The foil was just a test and I'm probably going to take that stuff out of there. I'm running cut-to-fit MSD StreetFire wires which claim "high EMI suppression" so I don't think that's the problem. Is there a way I can shield the head unit somehow from all interference? It's a RetroSound Hermosa if that makes any difference.

It seems like this comes up from time to time and after extensively trying to shield the head unit from any interference, it usually is something else. I'm not saying that it isn't interference, I'm just going off memmory from other posts.

Can you give more info on 'cutting in and out'? For instance, does it just get quieter, or static, or actually shut off. Is it only AM-FM, and if not, does it also do it on MP3 or CD?

Double check all of the connections, even at the speakers. Check the voltage at the radio with the truck running and the ignition on ACC.

[B. W.]

Jus spitballin' but is seems you have done everything to suppress ignition issues. Maybe the power to the radio is intermittent when the key is in the "on" position ( you've confirmed it works in "acc" position) possible bad ignition switch? Hotwire to 12v power (bypass ignition switch) if it still cuts out then at least you've eliminated the ignition switch! Hope you get it figured out.

Bobby

[dazza]

Also, I'm not sure how loud you listen to your music or if you have an amp, but too much will make it cut also. I had the same problem although it did it with truck off and key at ACC.

[StoningtonQB]

Originally Posted by BrianG

It seems like this comes up from time to time and after extensively trying to shield the head unit from any interference, it usually is something else. I'm not saying that it isn't interference, I'm just going off memmory from other posts.

Can you give more info on 'cutting in and out'? For instance, does it just get quieter, or static, or actually shut off. Is it only AM-FM, and if not, does it also do it on MP3 or CD?

Double check all of the connections, even at the speakers. Check the voltage at the radio with the truck running and the ignition on ACC.

The sound will go in and out. Full volume to mute. Radio and Bluetooth. I've been reading RetroSound's website and it looks like the issue may be the USB cable. Apparently it acts as an antenna for interference. I'm going to see what I can do with that tonight. It's 3 feet long and not detachable. They say on their website that going HEI with these radios are a problem because of this cable (which I don't even use).

I'll check this out and report back.

[StoningtonQB]

UPDATE... Aluminum foil does the trick! I tied up all of the leads from the head unit and enclosed them and the head unit inside a sheet of aluminum foil up behind the dash... took away 80% of the cut out. Now that I know that I'm on the right track, I'm going to buy something a little bit better than aluminum foil to wrap around, and will also get some ferrite core RF chokes for the power leads as well as the USB cable. This combination should eliminate all interference.

[slikside]

Great news!

Thanks for posting your fix.