Hey everyone have a really bizzare electrical problem with my Idle Stator switch and my Radio. Hoping someone can help. o No: FYI - I have a '66 Skylark with the 300 motor and ST300 2-speed transmission. There are 2 major electical components with the ST300, the Idle Stator Switch and the Stator-Detent Switch (the Switch/Pitch kickdown arm that connects to the carb). The Idle Stator Switch is the switch that is connected to the back of the acclerator linkage, and honestly, I have no idea what it does, but I know it's adjusted properly per the Service Manual. The Stator swich is connnected to the Detent, and it appears they both recieve power from the orange accessory wire on the same circuit as the clock, cigarette lighter, interior lights, and in the case of my car, the accessory power for my USA-6 Custom Autosound Radio. So here's the strange problem - whenever I tap the acclerator from idle (which engages or disengages the idle stator switch), i hear a pretty noticeable "POP" in my speakers. The 'POP' gets louder based on the volume of the radio. And I know it's the Idle stator switch causing the problem because I disconnected it and the 'POP' goes away. Plus, it's the only electrical component attached to the acclerator linkage. So, can anyone explain *why* the engagement of the switch would cause a 'POP' in my speakers? And more importantly, is there anything I can do to stop this from happening? It's a pretty recent development I think beacuse I never noticed it before. Thanks!
It's the stator solenoid. Actually, one of the ways to test not only the stator solenoid, but the downshift solenoid is to tune the AM radio to 1400 between stations and apply 12 volts to the solenoid connection at the trans. A "POP" in the speakers indicates the solenoid is working. Do you hear this on FM also, on all stations?? Might be the solenoid itself is putting out more of a signal, for some reason. Check you antenna connections at both ends for tightness. Not sure what else to suggest, maybe some one else would know.
I hear it on FM, and with the CD changer working, so it doesn't apper to have anything to do with the radio tuning, just so long as the radio is turned on. If it's a voltage spike, is there some sort of regulator or capacitor I could put in-line to make it stop? Is there any other way I can test to see if the switch is working? Thanks I know this is a strange one...
It's an inductive voltage spike from the current in the coil starting then stopping suddenly - same principal as your ignition. You will need to add a diode, reverse biased across the coil (or switch, doesn't matter). This will act to absorb voltage spikes, not sure of the part number though.
You could use a 1n4004- common rectifier diode available anywhere. Put the line side toward the + connection. What this does is bypasses the negative kickback from the coil and shorts it out. I would also add a suppressor inline with my radio power lead- available at radio shack. It's basically just a big coil to filter the DC. ________ Portable vaporizor review
20-amp Noise Filter $21.99 Brand: RadioShack Catalog #: 270-055 20A DLX Noise Filter (270-0055) Specifications Faxback Doc. # 9645 Input:..............................................................12 VDC 16 VDC Max. Output Current:...............................................20 Amps Max. Output Voltage Drop at 20 amps:...............................0.6 VDC Max. Attenuation:........................................1000 Hz, 35 dB +/- 10% 4000 Hz, 45 dB +/- 10% Input Lead Type Length +/- 10% Color AWG #16, 1015 155 mm Red+ 600V, 105C Black- Output Lead Type Length +/- 10% Color AWG #16, 1015 155 mm Blue+ 600V, 105C Black- ________ Suzuki Mr Wagon
Well, unfortunately that didn't help. Went and picked up the Radio Shack noise filter. Installed it per directions to the radio - same problem. I then installed it in the engine compartment, inline with the power to the detent switch, same problem. I'm still 100% convinced it's something with that switch. During the course of testing (I can tap the accelerator pedal and make it POP), the fuse blew. There's not much on that fuse; the wiper motor and the kickdown switch are the only things powered on that line. I can't find any physical connection between that switch and the radio, so I'm completely out of ideas o No: Any other suggestions?
test voltage in the circut, tap the gas and see what happens; does it spike (probably)? I don't think it would cause rf interference. But i'm 18, almost 19, so I'm still a young gunner. :3gears: -matt
What he said. The filter will help, but it doesn't take care of the problem. More like a band-aid than a solution. The diode should shunt the noise at the source. If it's a high voltage spike (which it will be if it's coming off a coil) the filter won't be able to attenuate enough to fix the problem. Plus, since it's a negative going spike, it is probably riding in on the ground line. If you look at the schematic for the filter, there is a coil in the + lead, but the negative lead is direct. The solution is the diode, with the filter to kill the rest of what's left. Sorry I wasn't clearer about that. ________ MOTORCYCLE TIRES
I will try the diode tonight. Further questions and clarification - First, should I hook the diode up to the power line going to the swtch? I'm 100% sure the problem is coming from that. When I disconnected the orange lead to the switch, the problem goes away. Second - I was testing today and I realized that the POP is *only* coming when playing the CD changer. There is no POP when listening to FM radio. In addition, I think it has something to do with the switch in the *transmission* now, because it acutally happens whever the pitch kicks in - either at idle or acceleration. So I can make the pop happen either way... SO STRANGE!! o No:
There are two seperate solenoids in the transmission, one for the switch pitch, and one for the kickdown. You say you hear it when playing a CD. This wouldn't be one of those add on changers, that play through the radio, and require you to tune to a certain frequency?? If so, that is the problem, and that is normal, nothing wrong with the solenoids or wiring. You'll have to resolve this with the diode or filter.
It's a CustomAutosound CD changer that plugs into the deck which has CD control. There is no other ground or anything for the CD changer; all power and everything comes from the Deck. I tried the diode tonight, plugged in between the power line and the switch, no help at all. Anything else? This is really annoying! <grr>
AAARGH!! OK get this. I think about the problem some more, and it dawns on me maybe it's a ground problem since it only happens with the CD. I go hookup a temporary ground to the case of the CD changer, turn on the car and *presto* problem gone. GREAT! so, I wire up a more permanent ground solution to the case of the CD changer turn the car back on, and everything is fine. Take the car for a test drive and, POOF, no heater motor. Fuse is blown. Maybe it's a coincidence I think, so I pop in another fuse, turn on the motor, and POOF blows again. ou: Now, I know the heater blower motor is on the same circuit as the the power for the kickdown switch that was giving me the problem. But what the HECK does that have to do with grounding the case of my CD changer? I can't physically undersand what the radio has to do with the heater motor since there is no physical connection to the two. This is driving me nuts. PLEASE any suggestions?!?!
Well, the search continues. I'm back to square one. I solved the heater motor problem (turns out that one of the wires I'd run through the firewall for the tach had caught underneath the blower resistor on the heater box, frayed, and was shorting out the motor). Why that turned up now I have no idea. Cleaned that up, put a loom over the wires so they won't short again. So, one problem down. After spending an hour or so cleaning up some of the rats nest (tying wires out of the way, cleaning up some questionable connections, etc.) I thought I was home free. Start the car up, heater motor is fine, turn the radio on sounds great, turn on the CD player, hit the accelerator and *POP*. The sound is back again. I've physically checked the wires and cleaned up a bunch of connections. Diode nor filter seem to work. Again I'm completely stumped.
The diode needs to go ACROSS the solenoid, not inline with the wire. The side of the diode with the bar MUST go to the + side, or you will short out the solenoid. What this does is provide a path for the negative spike off the coil to short itself out. Since the diode only conducts one direction and the spike is in the opposite direction of the power hookup normally applied, it will short out the spike, but not the power. It's odd to see it on an oscilloscope- these spikes come off when the power to a coil is removed and can be 100's of volts, even off of a low voltage supply! ________ Temperature For Vaporite
Back in 1976 I had a 66 LeMans. Everytime I kicked it down in to passing gear I'd blow the fuse in the wipers. So I just disconnected the kickdown switch at the gas pedal.
OK, pretend I'm a total newbie and explain what it means to go *across* the solenoid. :laugh: I'm not sure how this gets wired since I've never done this before. I've attached a very basic drawing of the switch and wiring - can you tell me where it should go? Thanks!
It sounds to me like you are experiencing noise from a poor ground, likely to the solenoid. I suggest checking the voltage to ground from the negative side of the solenoid. If this tests ok, by putting the volt meter leads between the ground for the solenoid to the ground side of the solenoid, and energizing the solenoid, you should see less than .3 volts. Any more indicates a problem with the ground side of the solenoid connections. You might try a capacitor across the solenoid leads. Obtain an electrolytic capacitor from Radio Shack or electronic supply store, something on the order of 470 uf, and connect the + side to the positive side of the connector, and the - side to the ground side of the solenoid. A capacitor will "store" the spike causing the pop, possibly eliminating the noise. Since the pop occurs on all functions of the stereo, it is likely on the battery side of the incoming power. If you are using an external amplifier, this is likely the source of the noise. Be sure that the positive battery leads are connected from the same point in the circuitry to both the head unit and the amp. More importantly, be sure the grounds are tight and tied together, to a common point, preferably to the battery negative. If using an external amp, it may be necessary to use what is known as a ground loop isolator, which goes between the head unit and the amp. Try the ground side first, then try using the capacitor to the + side of the head unit, similar to the set up on the solenoid. If necessary, I will need to know what equipment you are using, and EXACTLY how it is connected. Let me know...
