Strange Voltage
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Intermediate
Joined: May 2007
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Strange Voltage
My 98 suddenly stopped running. At first I suspected the fuel pump since there was no fuel in the rail. But after applying 12 volts directly to the pump I quickly ruled that out, ran fine. Next I checked all the fuses and relays in the fuse block. The fuse for the fuel pump was only out putting 7.5-8 volts the other two fuses right next to it also read 7.5-8 volts, all others were normal. Any ideas on where to go next?
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
My 98 suddenly stopped running. At first I suspected the fuel pump since there was no fuel in the rail. But after applying 12 volts directly to the pump I quickly ruled that out, ran fine. Next I checked all the fuses and relays in the fuse block. The fuse for the fuel pump was only out putting 7.5-8 volts the other two fuses right next to it also read 7.5-8 volts, all others were normal. Any ideas on where to go next?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
CHECK YOUR IGNITION SWITCH! 
I bet you a cold one that its hosed! I have a ignition switch repair post that explains how to repair and restore it. Thats a PRIME suspect for flukey lower than normal circuit voltages. Try rapidly turning your key on/off,on/off a few times and see if that changes symptoms.
You can also measure all the voltages at the fuses that are supplied by the ignition switch when it is in the HOT IN ON AND ACC position. You can also see if the pump runs in the CRANK position. Thats another dead give away of a bad switch!
BC
I bet you a cold one that its hosed! I have a ignition switch repair post that explains how to repair and restore it. Thats a PRIME suspect for flukey lower than normal circuit voltages. Try rapidly turning your key on/off,on/off a few times and see if that changes symptoms.
You can also measure all the voltages at the fuses that are supplied by the ignition switch when it is in the HOT IN ON AND ACC position. You can also see if the pump runs in the CRANK position. Thats another dead give away of a bad switch!
BC
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
Have you checked the state of your battery? You need a solid 12.6 vdc to get things to run. Battery connections at the battery and at the starter. If you can, pull the codes. The ignition switch may also be a source of issue.
6th Gear
Joined: Dec 2008
Posts: 6
Likes: 0
Check the condition of the wires (in harness bundles) just below the battery (in stock location) Many times, battery acid leaks out of the posts, drips onto wire bundles, eats through wire insullation, etc. Hose those wires down with alot of water, see if the problem 'changes' in any way. If so, get to those wires. Good luck.
Tech Contributor
Joined: Jan 2007
Posts: 19,493
Likes: 1,178
From: Dyer, IN
Check the condition of the wires (in harness bundles) just below the battery (in stock location) Many times, battery acid leaks out of the posts, drips onto wire bundles, eats through wire insullation, etc. Hose those wires down with alot of water, see if the problem 'changes' in any way. If so, get to those wires. Good luck.
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CHECK YOUR IGNITION SWITCH!
I bet you a cold one that its hosed! I have a ignition switch repair post that explains how to repair and restore it. Thats a PRIME suspect for flukey lower than normal circuit voltages. Try rapidly turning your key on/off,on/off a few times and see if that changes symptoms.
You can also measure all the voltages at the fuses that are supplied by the ignition switch when it is in the HOT IN ON AND ACC position. You can also see if the pump runs in the CRANK position. Thats another dead give away of a bad switch!
BC
I bet you a cold one that its hosed! I have a ignition switch repair post that explains how to repair and restore it. Thats a PRIME suspect for flukey lower than normal circuit voltages. Try rapidly turning your key on/off,on/off a few times and see if that changes symptoms.
You can also measure all the voltages at the fuses that are supplied by the ignition switch when it is in the HOT IN ON AND ACC position. You can also see if the pump runs in the CRANK position. Thats another dead give away of a bad switch!
BC
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I was at work when I made the first reply so I couldn't spend too much time replying to the post. 
Here is the link to the ignition switch repair post. Hope it helps solve your issue:
http://forums.corvetteforum.com/c5-t...ch-repair.html
Let us know what you find with the switch repairs.
Bill
Here is the link to the ignition switch repair post. Hope it helps solve your issue:
http://forums.corvetteforum.com/c5-t...ch-repair.html
Let us know what you find with the switch repairs.
Bill
