99 k1500 silverado

hi iv'e got a 99 k1500 silverado new body style with the 5,3lit vortec engine. my problem is i turn the ignition key on, and everything is fine. lights
come on every gauge reacts and iv'e got plenty power.When i turn the key to start the engine nothing happens.somtimes i have to flick the key about ten times before it cranks over. it starts at once. and then everything works fine for a week. i can hear the fuel pump running, and the clicing of some relays.it's just the last step that fails. anyone got any ideas?? faulty ignition switch maybe??? in advance thanks
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Yes, It takes about (usually 700 cold cranking amps of battery to spin over a motor.) if you battery is weak it will light all the lamps, run the fuel pump and turn on everything, but when you hit it with the starter motor there just isn't enough cold cranking amps left to spin the engine over.
Sometimes this can be indicative of a corroded set of BOLTS which on the Chevy battery posts.
So if you undo the battery terminals (bolts) and examine them carefully with the rubber pulled back, if you see any GREEN then this MAY be your problem. that includes any and especially any Green/White corrosion in the BOLT THREADS. This problem may be fixed by a new battery, but not for long, Sometimes the battery bolts may be warm if you try to crank it as the resistance of the corrosion heats up like a big resistor.
I had my 87 Chevy do this and strand my wife, I replaced the battery and got it home, next morning same thing, it was corroded terminals on the battery.
The other one I have seen is an alternator which is shorted on one side of it internal diode bridge, This makes the alternator put out a half wave rectified signal instead of a fully rectified waveform, So it charges the battery but only at half the available alternator output. So the battery stays sort of charged, but not enough and the battery doesn't seem to last as long either. so if you put a meter across the terminals of the battery when the truck is running, the meter must read at least 13.5 volts, and if its not then you may have a shorted diode in your alternator (there are 4 in a bridge)
See if any of this helps.
--
JAMES HAYES
"Leif Magne Berg" < snipped-for-privacy@frisurf.no> wrote in message
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Sounds like your starter is going. Auto Zone tests for FREE.

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ive replaced the battery in february. and the battery posts look fine. maybee i'll take a look at the starter. THANKYOU GUYS

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Leif Magne Berg wrote:

Goto Autozone, have them do a battery/alternator check. Check the connection at the battery and the starter (I had this on my 93 jimmy somehow the bolt for the hot cable had come loose and I had a bad connection at the starter) Then check the fuel pressure, for the all annoying chevy fuel pump.
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it was the points in the starter relay that sits in the under hood relay boks on the left side. opened the relay carefully and grinded the points whith som very fine paper.

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It could be starter soleniod conections too. I just had that problem this week on my 2000 K3500 (old body style). After only 38k miles the lead that powers the solenoid to engage starter (smaller wire) was badly corroded at terminal and the nut was so wasted that I had to break lug off stud and put a new one on (never had this happen before in over 35 years). They sure are using cheap materials these days. I am replacing the whole starter assembly with a new lifetime warranty one so if this happens again it will be replaced. (the old starter is starting to corrode bad in general too) Normally I just rebuild them but this one looks bad. Mine was doing same thing sometimes it would start and then not start. There was just enough resistance in the lug connection to drop the voltage just below the soleniods threshold and prevent it from starting at times. (the soleniod needs about a minimum of about 9.5 volts to fire reliably and I was getting 11 volt on wire there but only 8.5 to 9 volts made it to terminal stud itself thru corrosion. If you jumpered the car it would start because it raise system voltage enough from other car running to overcome resistance in connection and start.
On Sun, 23 Jul 2006 22:35:58 +0200, "Leif Magne Berg"

The SnoMan www.thesnoman.com
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