NEED ELECTRICAL HELP BAD!

well i'm pissed! i just put the new 65 dollar alternator on. and the biotch left me walking again. it is still doing the same thing. i don't know what the hell it is. i am getting very irritated with this truck.

Couple ideas for you. Do you own a voltage meter? If not buy/borrow one. Set it up so that you can see it while driving. Get the truck started and do what you have to so that it is at a drivable height, then shut the pump(s) off. Hopefully, it will be daylight when you do this. Once engine is running, observe voltage - should be 13 volts minimum. My stock 1990 alt runs at 13.9 to 14.2 w/o accessories on. Drive around block or some other nearby area where you can turn left and right, stop, start. Keep an eye on voltage. If minimal change, try with parking lights on (Turn signals should show approx .2 volt change during use). If you are still around 13.5 volts, try with headlights. What I am getting at is are there any shorts in system that might not be obvious without the volt meter (i.e. big volt drop on bumps, left turns, headlights only, etc.). if all is ok, try running the pump(s). Depending on what you have, you should be able to maintain a minimum of 12.8 volts when pumps run. If you go below 12 volts for any length of time (5 minutes?) it is possible that your battery is getting seriously drained.

Sorry for the long post - hard to describe in words. let me know if this helps.

i have noticed that it dies when the compressors kick on. it only seems to do it when i have the lights on and playing with the switches and make the compressors come on. do you think that there might be a short in the wiring for the compressors. this is a very weird deal. usually whenever i have had a short i blow a fuse or something but this thing just starts losing all power. it is very hard to explain. but when i am driving with the headlights on and the compressors kick on, i watch the gauge lights go to about half lit then blank, then the whole truck dies, and has no electrical power at all. but then it will jump right off and i can drive it for a little while longer. is there any chance that it could maybe be the ignition coil? that is an idea a friend of mine gave me. i don't know anymore. i think i am about to just end up buying a bunch of new parts and install them until the problem is fixed.

check the grounds on your compressors, where are the grounded to? i would move them to the frame (better ground), when the ground is weak the voltage drops and the ampreage goes up, mosty caused by bad grounds, and i would that the altenator and get it beefed up as much as possible

If it jumps and is good to go then it's probably a dead cell. Definatly have the battery tested. And like said before, get an optima. $160 sounds like a lot for a battery but you will be very happy you did. Or wishing you had - like me.

mike, i will check my grounds tomorrow. thanks.

lostb2200 i had the battery tested already and it was good. i may still get an optima though. someone correct me if i am wrong on this though. i thought that all the battery is for is to get the vehicle started. after it is running the alternator takes over and the battery is no longer in use. am i right on that or wrong. i also think that it kind of acts like a back up for the alternator when you are using a lot of power. ie. a stereo system. when the bass hits and the alternator doesn't put out enough power it gets power from the battery, then the alternator charges the battery back up. could be wrong though.

Dead on! Battery is storage - does not generate. Alternator creates power, but does not store power. Point I was trying to get at with the testing was where the problem was (compressor, lights, or?) If there is a bad ground or short and the requirements exceed the available supply of power (either alternator, battery, both) then there is not enough left to fire the ignition coil. Plugs foul out, engine dies.

ok so it could still be the battery then too. man i thought this was going to be an easy week and i should be dragging this thing by now. haha.

ok i went to look at the comperssor grounds like mike said and this is what i found out. this is how they are wired up. please excuse the drawing, i suck. haha.

i looked at bagginit.com and this just looks wrong. i am not sure how they are even reading the low pressure and how everything is working. please help.

Yeah that one little ground is not good enough for both of your compressors. Rewire your compressors so they are grounded and use your pressure switch to turn the relays on and off with a positive wire.

That right there might be your problem. Basically it looks like your compressors have 12v on them all the time and the pressure switch is grounding them to make them come on. That pressure switch cant handle the current trying to run thru it.