lights pulsating

[stock91w350]

all the lights in and out pulsate non stop at idle, any ideas?

[Ace]

Voltage regulator and/or grounds thereof.

[Richie O]

I told the last owner to put one on. I guess he didn't. The last time I saw it it was doing the regulator dance.

[stock91w350]

thanks guys im on it

[ccoxva]

Hate to bump a thread this old but..... My truck is doing this now, I first thought the v reg but just replaced it and didnt change a thing. I'm pretty sure my grounds are pretty sound. What would be the next option???

[Mark Nixon]

Check your battery's overall condition, load test, specific gravity, etc.
Also make sure your connections at the alternator AND the connector plug on the wiring are clean and at least greased and well-sealed.
The alternator can also be getting worn on the brushes and commutators, have it spun and load tested by a GOOD shop. O'Reilly's, etc. isn't a good choice for true diagnostics on them.

Also, there are good regulators and bad ones, I will hunt high and low to acquire a good OEM Mopar one in good shape, long before I will bolt on a cheap replacement from the sources available.
I never throw old OEM ones away and it's saved my ass more than once.

Mark.

[ccoxva]

Thats something else forgot to put, the bat is 1year old deka commercial and I checked it and it is at 1300cca still. And its still slow to start anytime the grid heaters have to come on. Thanks alot for your quick input..

[Mark Nixon]

...And its still slow to start anytime the grid heaters have to come on...

Slow to start in what way?
Starter speed, or length of cranking time?

Mark.

[ccoxva]

Just sluggish rollin over. Starts fast when it'll turn it over good like they all do. This is prob nothing to do with my electrical issue its prob the advance auto starter I stuck on there in the summer.....

[Mark Nixon]

Check the positive terminal and the 2 wires that are molded into the terminal clamp (as factory), then check the smaller wire from the battery clamp to the connection point that goes into the wiring harness.
Also, do a voltage drop test on the positive cable, at the starter terminal, to see if there may be resistance due to corrosion.
It should have very little, if any, difference from a direct test at the battery.

Mark.

[ccoxva]

Thanks man for your time it is very much appreciated. I will do that in the next couple days and post my findings.

[manyholes]

i had that issue with headlights and dome light, ect when i was out visiting my mom. i took the truck to the local car wash to clean up under the hood, got back, pyro wouldnt read, couldnt get proper power, all the dash gauges doing a dance. popped the hood, cleaned all the grounds, started taking connectors apart to clean them with electrowash(cleaner from work for my electircal crap there ) there was an orange wire on driverside inner fender close to the hood hinge that when i touched the conector the lights would flicker on, i grabed the wire and it fell right out, full of corosion, threw out the connector and spliced in a jumper wire, all good now. that was my gremlin there. the orange wire came out of a large wiring loom and had maybe a few inches of wire before the connector. good luck