When I was driving home today I noticed when I hit the brakes the head lights dimmed alot. So I got up to speed and hit the brakes again and watches my guagues, sure enough instead of being 14.5-15 like normal when I hit the brakes it droped to like 12.5-13 then caught itself and went back up.

I had my headlights on, and my heater on full blast. Thats it, no other accessory lights or anything. When I turned the heater off it solved the problem but the reason I'm thinking something is wrong now is because in the past I can have my subs blasting (2000W amp) and my headalights on and they would never dim and the gauge wouldn;t even flinch. Maybe I just need to throw the bat on the charger for the night? I only drive my can usually for like 10 mins to work and around town.

And its a 1000 cranking amp battery, so shes pretty hefft.

 

Check the output on your alternator with a multi-meter. That should help you determine wether or not it's the cause.

 

sounds like the alt. or the voltage regulater... but im pretty sure the regulators are built into the PCM's .. the older cars and trucks had a remote VR or a built in VR in the alt. like Rom said.. meter the output and becarefull.. itll suck to get your leads wrapped up in the belt or fan.. have someone rev it for you and switch stuff on and off.. try to pull a large draw off of it.. and if it dips way down at low idle.. then you tracked it.. and i know my 01 sport offroad alt. cant be rebuilt b/.c its a HO .. 130amp output...and they are FRIGGEN expensive too.. but it maybe worth it if you got a big system to get an offroad model alt. not sure if itll bolt up to your braketing.. but it wouldnt hurt to try it out.. goodluck!!!!!!!!!!!!!!!!!!!!!!!

 

I'll play with the multi meter tomarrow, I have one of those HO 130amp alts too [&:]

 

take it to Advance Auto/Autozone or any parts shop that will test your alternator the right way. it may be fine (as you already know) w/o a load but under load it may be crapping out. the tester will be able to put a load on it and let you know if it's ok or not.

 

Well I haven't got the anternator checked yet but I had another interesting problem today....

First off it wouldn't start, it would barely turn over. So again this kinda points to the alternator not charging the battery. I hook up the jumper cables, wait a few mins and go to start it. At first there was no change, it would BARELY turn over, then all of the sudden it just instantly started cranking and full-speed and it started right up. I thought that was kinda odd...it didn't start turning over faster or anything, but just instantly went from slow, to cranking full speed. Anyways I throw the battery charger on it and it only was drawing 2.5 amps. Yet again kinda wierd, this suggests the battery is charged. But I let it charge all day for the hell of it and come home its drawing only 1 amp. (Yes I wiggled the clips, no corrotion on them or anything, I'm not dumb )

Anyways I go to start it, starts right up no problem. Except for the fact it idled at 1800 RPM for about 10 mins. Then I was standing in the garage and I heard it dip down to about probably 900 RPM for a few seconds, then right back up to 1800. Sat at 1800 for a few seconds, then back down to 900ish. Kept on going up and down untill I shut it off like 5 mins later.

So the reason it wouldn't start, I'm thinking the starter actually, not the battery. It did sit for about 36 hours w/out being started out in the cold.

And for the crazy idle, I have no idea. I checked the codes and unless I read it wrong I got code 14, something with the MAP sensor. But it says the CE light would be on when its running if that code was triped.

Wierd stuff, any ideas? I'm still gonne check the alternator.

 

Just had the Battery and Alt checked, both are fine.

Drove it to AutoZone and back, put it in park and now it only idles at 1200 which is still abnormally high. I checked a couple vaccuum lines but I have to get the diagram and check them all. Kinda funny though, seems like my truck is acting up all at once. On the way to AutoZone it didn't want to shift into 2nd on the way there and back. And when it did it was really rough!

 

what happend to the outside temps? did they dip pretty good? next time it doesnt want to start right up and crank slow, take a blow dryer to the starter and put some heat into it. after a couple of minutes of heat, try and start it... if it starts easily, then you found your starting problem.

the idle however is controlled by the IAC motor... it could be sticking. if you leave it that way long enough it sould throw a code. I had to drive my truck last year for abut 3 or 4 miles with a real bad miss before it thru a #2 cylinder miss-fire code.

 

I'll have to try that blow dryer thing. Its been about 20 degrees out. It started right up this morning, and oddly enough the idle is back to normal. Crazy cars, I tell ya....

Last year we had some -15 mornings and I had no trouble starting it at all. Also the idle was elivated during those really cold days, but npt even close to what it was yesterday!

 

With my last truck I smacked into the back of some guy one day, Kept driving the thing for a while, the alternator belt squeald like hell for about a week or two then quit...So I was like "cool"...Then one day as Im cruising down the interstate at 80 mph I feel the engine start to putter out like it would if you ran out of gas.... I was pumping the clutch just trying to get off the interstate...Well, long story short it stopped on the access ramp.... Wasnt fun to push the damn thing off either.. Once it was off I had to call my brother to come find me.. I sat there for an hour and half NO RADIO or anything considering the damn truck was DEAD....


So my advice... Get the alternator fixed quick, dont blow it off like I did.