Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Fuel pump voltage question

Thread Tools
 
Search this Thread
 
Old 09-07-2019, 06:44 PM
  #1  
Member

Thread Starter
 
cougar20th's Avatar
 
Join Date: Jun 2000
Location: Amherst NH
Posts: 125
Likes: 0
Received 1 Like on 1 Post
Car: Black 88 Iroc Convertable
Fuel pump voltage question

What is the voltage reading I should get at the three wire plug that is above the differential for the fuel pump.?
Old 09-07-2019, 08:37 PM
  #2  
Supreme Member
iTrader: (1)
 
GeneralDisorder's Avatar
 
Join Date: Mar 2017
Location: Portland, OR
Posts: 4,255
Received 422 Likes on 323 Posts
Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: Fuel pump voltage question

0v when the engine is off, 12.5v with the engine off and a fully charged battery, and 14.5v with the engine running and a working alt. It should run momentarily when you key-on, then stop and wait for cranking or running.

GD
Old 09-09-2019, 08:03 PM
  #3  
Member

Thread Starter
 
cougar20th's Avatar
 
Join Date: Jun 2000
Location: Amherst NH
Posts: 125
Likes: 0
Received 1 Like on 1 Post
Car: Black 88 Iroc Convertable
Re: Fuel pump voltage question

Thank you. Ended up the pump was seized. So I had to swap it. Odd thing was the strainer had mostly dissolved some of the strainer was left and its mounting parts. , the rubber seals had turned to a sticky mess. On a 7 year old pump.
Old 09-09-2019, 08:10 PM
  #4  
Supreme Member
iTrader: (1)
 
GeneralDisorder's Avatar
 
Join Date: Mar 2017
Location: Portland, OR
Posts: 4,255
Received 422 Likes on 323 Posts
Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: Fuel pump voltage question

Originally Posted by cougar20th
Thank you. Ended up the pump was seized. So I had to swap it. Odd thing was the strainer had mostly dissolved some of the strainer was left and its mounting parts. , the rubber seals had turned to a sticky mess. On a 7 year old pump.
Sounds like it may have not been Ethanol safe. Or was really poor quality. I generally use the Deatschwerks DW200 (255LPH) pumps - they have a kit for the C4 Vette that fits alright. I usually just buy a new pickup/sending unit assembly (Spectra seems the better of the two out there) and those also come with strainer bags, and hose, and such.

GD
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Frozer!!!
Electronics
1
10-12-2007 09:31 PM
Notplayn
Electronics
0
08-25-2007 05:29 PM



Quick Reply: Fuel pump voltage question



All times are GMT -5. The time now is 02:07 PM.