After trouble-free driving for quite some time, my truck decided to randomly die at a green light today, a few times, in a disturbing manner.

It happened when I hit the gas after a red light, and felt like the electricity was cut for a moment and the truck was bucking, the ABS light came on, and the radio flickered off for a moment. The thing never stayed completely dead.

This wasn't a sputtering, fuel related misfire type event, and seemed to be related to the motion of giving the truck a little gas. Shifts fine, revs fine in neutral. I restarted it and went through this process a few times before getting it to roll gently enough and taking off down the road.

I also got some flickering of the radio on/off when I hit a few sizable bumps, so this to me seems electrical/loose connection....somewhere....and I was unable to get it to repeat for the remainder of my 10 min drive home (honestly I was trying to get home more than trying to stall). I suspected loose battery terminals, they are not in great shape, but they're on good and tight.

Starts up fine, idles smooth. 3/4 tank of gas. No CEL's before, during or after the ordeal. New battery, new plugs, both with a few weeks of trouble free driving on them.

Anyone experience something like this? Any ideas where you'd start?

@Greaser ; it seems to me like a ground issue check the grounds by the battery and on the motor, they have to be clean an tight. Since you already suspect a connector check all of the connectors in the engine bay that they are good and tight.

I would clean the terminals really good and verify all your engines grounds are good and clean and make sure your alternator is functioning properly and your voltage is where it should be. It's really sounding like your power is fluctuating with some dity engine grounds or your alternator isn't producing power properly. At idle what's your trucks voltage?

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If you don't see any code, it could be a failing fuel pump.

When cleaning the terminals and the ground connection look at the Batt. Cable wires they maybe in pretty bad shape too.

That's not going to make the lights flicker. It's a major connection issue, as the others have said. In addition to the advice given, inspect the cables themselves, looking for any bubbling of the insulation. That's a sure sign of bad corrosion inside. If you have any bolt-on terminals, get rid of them. Also make sure no hardware is loose in the battery area and that the holddown is well separate from conductors and screwed down tight..

^^ Good point.

Thanks Durk!

After confirming battery terminals good....The ABS light can trip from a failing alternator, which can also cause weird things like lights getting bright and dimming and things getting wacky. Watch for a quick battery light flicker, that will trip ABS light which then will stay on even though battery light is no longer on. Run a voltage meter on your battery positive terminal while running and see for fluctuation, should be about 14 volts when charging properly.
The fact that you noticed related to when giving gas (which changes alternator speed) leads me to think failing alternator is good possibility.
Also run a forum search (battery light and ABS light) kind of a common thing relating to a failing alternator.

Thanks all for the responses. Swapping out battery terminals/checking grounds tomorrow (was on my list anyway) and checking out the 'fuse link' I think it's called, as that seems like a good thing to check as well.

Alternator is now on my list too, it's probably the original, but I'd think I would see some dimming, charging light or battery drain if it were struggling and I don't know if that would be likely to act up when hitting bumps, but who knows.

Before you go too far, load test the battery and confirm level of charge. Do that BEFORE you mess with the alt. The alt can kill a bat. Once dead, a new/fixed/rebuilt alt is useless without a new battery.

I make it a rule to confirm battery health very early in this process, like right after checking terminals are tight. You can waste a lot of time otherwise.

I can confirm that the ABS light will come on if you have funky volt reading. Mine seemed to come on above 16 or 17 volts. One of my connections to the alternator was corroded and getting high voltage spikes everytime I washed my car or it rained. Sounds like a connection somewhere is giving you trouble. Mine never cut out or lights dim, just the scan gauge telling me my volts were 16+.

If the original alt has 180k to 200k on the odometer. Your brushes will be very warn out anyways. As that's about the average length of time for both the alternator and the starter brushes. [ well that's what I seen in all the Toyotas I owned and worked on for 30 years] it's an average though sometimes its longer and sometimes its slightly less.


All the posters gave excellent advice. I am sure you soon will have your cause.

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I like spraying this stuff on my corrosion prone connections, battery, starter, alt. Works good. Get this at Autozone.

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I use dielectric grease myself.

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For plugs and connectors, sure. But for battery terminals and ground points, good old Vaseline is a conductor and works great. Dielectric does not conduct electricity. I keep both on my lube shelf.