Flickering Lights?????

[coupeownerBE]

Ok I got a 92 gt convertible that I just picked up.. I drove it at night for the first time and the dash lights and headlights..possibly the taillights also(cant see) are flickering.. not going off and on but just flickering.. when I come to a stop and the car going down to a idle. the flickering stops.. then I can rev it up a little and it flickers to the pulse of the engine???? help.. cant figure it out.. tested the battery and charging system. both are good. charging at 14.3 and the battery tested at 490cca..

 

[jrichker]

Make a trip to the auto parts store near you and have the charging system checked out. The chain stores like AutoZone & Advanced Auto Parts will do it for free.

 

[coupeownerBE]

I already checked the charging system. its listed above. 14.39 which is a little high but acceptable and the battery tested good 449cca out of 500cca.. so that's been checked. I was hoping someone would be like oh man that happen to me it was just "blahblahblahblahblah". just wishful thinking..lol.

 

[jrichker]

You checked the voltage, but you did not say what sort of load was on the electrical system when the voltage check was done. There could be other things going on that you did not observe.

 

[coupeownerBE]

good point. well I had the headlights on and while testing the voltage I rev the engine slightly to get the lights to flicker and watched for a change. it went from 14.38 to 14.40 and that was it..

 

[jrichker]

Turn everything on and try it again. You may be surprised. You either have an alternator problem or a bad connection somewhere. The stock alternator push on power plug has a habit of overheating and then causing problems. Check yours along with the secondary power ground that is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges. The clue to a bad ground here is that the temp gauge goes up as you add electrical load such as heater, lights and A/C.

The picture shows the common ground point for the battery , computer, & extra 3G alternator ground wire as described above in paragraph 2. A screwdriver points to the bolt that is the common ground point.

The battery common ground is a 10 gauge pigtail with the computer ground attached to it.
Picture courtesy timewarped1972

Correct negative battery ground cable.

See http://assets.fluke.com/appnotes/automotive/beatbook.pdf for help for help troubleshooting voltage drops across connections and components. Be sure to have the maximum load on a circuit when testing voltage drops across connections. As current across a defective or weak connection, increases so does the voltage drop. A circuit or connection may check out good with no load or minimal load, but show up bad under maximum load conditions. .

Voltage drops should not exceed the following:
200 mV Wire or cable
300 mV Switch
100 mV Ground
0 mV to <50 mV Sensor Connections
0.0V bolt together connections

 

[coupeownerBE]

very good info man thanks a lot.. ill go over everything and see what I come up with.. thanks again