Hello I need some help. Yesterday I was driving and all of a sudden my battery and brake light came on and I heard a sound from the bottom of the truck. It sounded like a cable hitting the frame or something in that nature. I checked underneath but everything seems to be ok. When I started the truck again I noticed that the truck was idling up and down and the whole motor was shaking. I checked all the connections and fluids and can't seem to figure out what happened. The truck runs fine, it's just when it idles it lopes. I just don't understand why the battery and brake light came on. The only thing that I've done recently is change the plugs, pcv, and air filter but that was 3 weeks ago and it's been running great since. Any input would be appreciated.

Thanks..

 

My 86 runner did the same thing once..It was the altenator. maybe check your belts. good luck

 

Those lights on together mean that your alternator is not working. Because of this your idle may rise up a bit because there is no resistance from the alternator. If your idle goes up to high when the truck is in "open loop" or warm, the idle will go up and down and up and down. Slow your idle down and that will stop but you still have a problem with your alternator.

 

take you alternator out and take it to the dealer or a reputable shop. probably just needs to be rebuilt. (new brushes, etc..)

 

You could just drive it up to your local autozone or whoever and get them to test it on the truck for free. If it's bad you're already there to buy a new one. They'll probably bitch about where it's located, I know I do.

 

Thanks for all the help....i'll keep everyone posted on what happened. also i removed the clearcoat from my SR5 wheels and they look real clean. this site is awesome...

 

Is the alternator easy to replace?? I've searched and was unsuccessful finding a how to on this..

 

Ya very easy. Just take off the intake tube and fan, loosen the tensioner for the power steering belt, take off that belt. Unplug the alternator, diconnect the battery, take off the power cable to the alternator, take the adjuster bolt out of the alternator, take the pivot bolt out of the alternator and pull the alternator out from the passenger side of the motor under the power steering pump and infront of the rad. I have done it twice in the past week as my brushes went out.

If it just needs brushes they are very easy to change as well. Just get them from a parts store and pull the back cover of the alternator. There are 2 screws that hold the brush holder on. Undue them and put your new brushes in. Make sure the grooves are not to deep in the shaft. If so you will need a new alternator.

 

I replaced mine in April. Not too bad of a job, but I went at it from the bottom so I had to take off the lower radiator hose and get a coolant bath.

Rob

 

doesn't sound too bad. i'll give it shot this weekend and maybe change out the belts since they'll be off.

 

My 95 only comes out from the bottom... Have to drain the rad and take off the lower hose.

Other than that it's cake.

 

If you take the fan off you can bring the alternator into the fan shroud and around to the other side. This will save you having to dump antifreeze and lay on your back.

 

I changed mine a month ago, just wiggled it around the hoses and pulled it out without unhooking anything else.

 

Mine does the loping thing too, had the auto zone guy test it, like less than an amp at idle...that's not right is it, kinda hesitant to know the answer cause then I would have an excuse not to buy one of those high output alternators LC Eng. has

 

did your brake and battery lights come on too??

 

My brake and battery light only comes on when I run it through a big mud hole I guess something shorts out to pull a lot of current?

 

Either that or your belt slips temporarily.