I have a '72 and installed an HEI distributor. Since then, my stereo has started cutting out. Sometimes it works fine, then it keeps cutting out. I have tried checking my grounds, installing a filter capacitor, connecting directly to the battery and even wrapping the radio with tin foil. The only thing that works is to pull it out of the dash a ways. A car audio shop suggested replacing the unit. It is a Jenson. I looking at a Pioneer DEHX6600BT. Any help would be greatly appreciated.

 

Do you have the distributor RF shield in place? Seems like a lot of folks remove this item and toss them out.

 

I have never had this problem so I am flying blind here but thought I would start the conversation up.
When you say cutting out do you mean the radio station drops, or the head loses power? Like I said, never had this problem, but would think that if it were an interference issue with the new ignition, it would create a buzz or whine in the audio but not cut out.
Sounds crude but can you turn the car on and reach the wires behind the head unit and wiggle them around to see if that is the source of the problem?
It would not be the first time that an issue is hard to track down just because of the timing of when it occurs. Ask me how I know. :-)
Hope that either helps, or gets the ball rolling so somebody else can steer you in the right direction.

 

When I bought mine the radio and speakers were gone. I replaced them with a cheap pioneer and 4 Rockford 4x6's. I had the same problem. I had run the driver side speaker wires over the tach and this is where I was picking up the noise. To fix I ran the driver side speaker wires toward the kick panel and on the under side of the dash right into the console. To diagnose, i had to disconnect the wires running to driver side and turn on the radio which made it work perfectly. Hope this helps

 

The shielding I have is not for the big HEI distributor, so it won't work.

 

The stereo volume drops very low for a moment, comes back up, then repeats the pattern over and over. I have checked and rechecked and rechecked, etc. the wiring. I have even set up another unit and had the same problem. If I keep the stereo away from the dash, no problem. Move it back, the problem returns.

 

My tach is cable driven.

 

I do appreciate all the input. My problem does seem unique. I'll let you know if I come up with a solution.

 

I went thru a similar problem when I tied in my stereos illumination wire to the dash lights, kept blowing the fuse when I turned on the lights.

I would suggest following the stereo guys suggestion and install a new deck. Hopefully you can borrow one from a friend and temporarily install one.

The first time you said it drops the volume and goes back up, I thought about the blue tooth in mine. Every time I get a text. thats what it does.

Ken

 

I'd check the speakers and then wires. If you have tried another unit -then that rules out a bad output. Either a bad speaker (voice coil rubbing) or a shorting wire would cause the problem you describe.

Disconnect one speaker at a time to check.

Richard

 

yeah, I don't think it's related to the new dizzy. Check your connectors at the back of the deck. Could be that the wiring twists a bad connector or pin at the deck when it's pushed back. This is real common with RCA's if you're using any.

 

Since the other unit is the exact same make and model, there could be a problem, in the design. I have done a rewire with no help, but when I put in a strong filter capacitor, it help some. I never needed that before the distributor change.

 

I've ordered a new unit from Amazon. Mine does not have blue tooth or an iPod hook-up, but the new one does. Hopefully it will solve the problem.

 

Then it's a speaker-just a coincidence w/ the HEI. Try hooking up one speaker at a time. If it had anything to do w/ the HEI- it wouldn't do it when the car was off...And it would be a constant problem- not like the one you are describing.

Richard

 

It works perfectly when the engine is not running.

 

Just trying to help- I was in the car stereo industry for 20 years.

I never saw what you described as anything other than a bad output on the radio-confirmed not the problem by using another unit- or bad speaker wiring -or speaker bad- as in voice coil rubbing-bad x-crossover network-or even speaker tensile grounding out on the speakers frame or metal part of the car or too low an impedance.

An educated guess- when the engine is not running- the voltage is down- therefore the radio doesn't put out as much power. The big filter also drops the voltage to the radio- so that's why that seemed to help.



If you want to buy a new radio-have at it.

Richard

 

Thanks for the input. I didn't mention that it was only a problem when running. It's hard to cover everything I've done in a few words. As I understand it, the filter capacitor doesn't drop the voltage like a resister would, but eliminates sudden impulses by providing a steady voltage. Obviously I'm no expert or I would already have solved this problem. It's not so much that I want to buy a new stereo, but that I'm frustrated with the hours invested for little return.

 

The filter is designed to get rid of unfiltered alternator AC current or "ripple" not filtered that passes by the rectifier in the Alternator. AKA "alternator whine" - A higher pitched sound that changes w/ engine speed- and usually gets louder if you turn on the lights/fan etc. You don't have that problem....

The battery BTW is the best filter in the world- and you hooked it up to that....



The HEI has nothing to do w/ this- HEI interference would be very prevalent if you listened to AM- as it is a RFI- radio frequency interference- a ticking noise that will also increase as you rev the engine. Again- that is not what you are experiencing.




I'm saying you are chasing the wrong thing- is the audio output of the headunit that is going up and down or rather cutting out. The output amp sees a short -heats up and turns off. It's a simple as that.



More than likely the new radio will do the same thing- as the speaker outputs are seeing a ground intermittently-some way- some how.



Here's an even easier diagnosis-you don't even need to disconnect anything.



If you have four speakers - you'll need to adjusted the fader all the the front- then go all to the left speaker w/ the balance- see if it cuts out- then to the right- then do the same w/ the rear speakers.


Let me know what happens-

Richard -"I use to be an expert"

 

I did exactly as you suggested, all left, then all right, than all front, then all back. The problem remained irritating there in all situations.

 

I should mention that it seemed the problem had decreased until I took it for a spin this morning. As I was driving, suddenly it grew worse and stayed that way. Now it is back to the "normal" problem. This is the other radio, which was new in the box, but is the identical model.