ive got problems with my alternator.when i start the car it has plenty of juice and the gauge seems like its charging.but after a few minutes of driving it starts to lose volts on the gauge and soon doesnt want to stay running.ive gone through 3 alternators and this one has checked out good twice.i have no idea what the problem is.any advice would be great guys!by the way its a 95 motor with afr 210 heads,lt4 intake,big isky cam,stock lenght comp pushrods,pro magnum 1.6 rockers,comp r lifters(wich suck),electric water pump,cloyes 3145 timing set,cat sfi damper,alternator relocation by speed specialty,58mm throttle body,42# injectors,slp cold air,bbk shorty headers,no egr,no smog pump,holly fuel pressure regulator,255lph granatelli fuel pump,msd cap and rotor,lt4 knock module,spec stage 3 clutch,fidanza aluminum flywheel,4.11 motive gears,t/a cover,lakewood traction bars,eibach drag launch springs,american racing torque thrust II's,315x35x17 back,drag radials,ls1 driveshaft,pcm 4less tuning,6 speed with a pro 5.0 short throw shifter.*****also just recently i have a vibe problem.when i hit the gas anything above 2 k and the engine starts vibing real bad whether its in nuetral or under load.diagnostic program says its retarding timing due to the vibes the knock sensor is picking up and im losing alot of power.any help would be great.thanks guys!

 

anyone have any ideas??????

 

Disregarding the gage, what is the voltage across the battery from the time you start until the time it craps out?

 

i have an idea...double spacing after periods...it's way too hard to read.

check your grounds for a loose wire or check the power wires for corrosion.

 

Seriously. Capitalization, too. No one is going to read or respond when it's so hard to read.

 

Sorry about the capitalization guys.Anyways the volts show about 14 when i first start it up and drop below 11 at finish.I checked the wires for corrosion and they are good.All new.I checked the battery ground to the block and it seems good.Any other grounds i need to check?Location of the grounds?
Thanks for the replys!

 

You either have some device getting hot and increasing it's load on the system which is highly unlikely. Or your alternator is crapping out as it gets hot which is very likely. The reason it checks out ok is it has a hot problem. If you were to check it again with a blow dryer heating it up as it was tested you would probably see the problem on the test bench.

Get a reputable alternator and not one from AZ or Advance. Even if they have a "lifetime" warranty. OE is preferable

 

Makes sense speedy.The alternator i have is from murrays.So are the previous ones that had the same problem.Thanks for the advice.