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Upon driving randomly the headlights will get very dim (never go off fully) at the same time the dash cluster will dim then within a second will be back. Strangely doesn't seem to affect the fogs or maybe I just don't notice. Never happens at highway speed just city driving, and the battery gauge doesn't dip while this happens. Also possibly related lately while city driving and again never highway speeds the car seems to randomly "buck" the RPMs will shoot up to 3000 then back to a normal reading for your speed (praying its not a tranny problem, perhaps wishful thinking). New plugs wires and battery within the last 6 months, everything's right tight and has a solid connection, nothing aftermarket leeching power etc. Thoughts?

Get an electrical system test done at Advance. It's free.

Bucking could be ignition coil.

MrJiggy716 wrote:Upon driving randomly the headlights will get very dim (never go off fully) at the same time the dash cluster will dim then within a second will be back. Strangely doesn't seem to affect the fogs or maybe I just don't notice. Never happens at highway speed just city driving, and the battery gauge doesn't dip while this happens. Also possibly related lately while city driving and again never highway speeds the car seems to randomly "buck" the RPMs will shoot up to 3000 then back to a normal reading for your speed (praying its not a tranny problem, perhaps wishful thinking). New plugs wires and battery within the last 6 months, everything's right tight and has a solid connection, nothing aftermarket leeching power etc. Thoughts?

What kind of condition is the car in? The under hood stuff? Has it been victim of previous coolant and/or oil leaks? There are many possible problems that could cause these type of symptoms. My thoughts are with the electrical system. Does the battery have a good connection? Are you using those "temporary" clamp on terminals? The car is aging and along with it is an aging electrical system. Previous work requiring disconnecting the main ground on the engine could be starting to fail.

Heat builds up in the engine compartment in town traffic and dissipates at highway speeds. Current or previous fluid leaks may be affecting something. A "Load Test" on a healthy battery should be able to handle 250 amp draw for 10 seconds without falling below 10 volts - A carbon Pile load tester is preferred over the hand held type. Autozone might have one and if you are lucky, they might have an employee who knows how to use it.

When the ghost in the machine shows up, look for grounding issues. These problems are easily overlooked and misunderstood. Grounding problems do all sorts of strange things, one can never predict what will happen with a grounding issue. Many look good on a multimeter, but fail under electrical load.

The car is in pretty good condition, I inherited it by chance and the previous owner was elderly and drove it sporadically (meaning it would sit for weeks at a time). I've had it for about a year and a half to two years. In which ive replaced a lot of parts fixed a lot of the common problems and kept up with it.

The battery clamps are the stock ones that came with the vehicle and are in good condition even cleaned them up although they didn't have any build up or corrosion, I was just being anal lol. Potential to be a ground I suppose.

MrJiggy716 wrote:The car is in pretty good condition, I inherited it by chance and the previous owner was elderly and drove it sporadically (meaning it would sit for weeks at a time). I've had it for about a year and a half to two years. In which ive replaced a lot of parts fixed a lot of the common problems and kept up with it.

The battery clamps are the stock ones that came with the vehicle and are in good condition even cleaned them up although they didn't have any build up or corrosion, I was just being anal lol. Potential to be a ground I suppose.

The GM side-post battery terminal design works great just as long as it isn't hacked up by doing things like adding audio power amp power wiring and such. The battery maintenance comes into play too. If there is a need to tap the power directly at the battery, it is recommended to get the double stack battery lug and another GM sealed side post cable, then power can be tapped from that one. Other alternatives include a battery with side and top post mounts and/or high quality aftermarket side post terminal lugs with the threaded bolt at the end for attachment. A new thread on electrical systems and wiring is currently under construction and will be posted here in a few days. This information is still relevant to the symptoms you mentioned.

Do you have a volt/ohm meter? If so, I can step you through a few simple checks and describe what the various readings reveal. The meaning of life is the mystery itself.. To know all is forbidden, that's why we have forums. :-)

I will have a shop test the battery and alternator, thanks for the tip. Although the problem of dimming persists randomly it does seem to be more frequent for ten or so minutes after start up or making a turn ...or...... I could just be paranoid and looking for a pattern when there is none lol

When it happens during a turn is it going around a corner or in a parking lot where the wheel is cranked. My car will dim all the lights and such if I crank the wheel to the max and will stall out if I hold it turned. I heard its bad to keep the wheel cranked all the way anyways so I never do it.