Fuel pump not running
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 1,036
Likes: 0
From: Plant City Fl
Fuel pump not running
Went to start my 88 today and could'nt hear the fuel pump run. I tried to start it anyway and it just turned over. Shut if off, turned it on again to see if the pump would run, but got nothing.
Do I suspect the relay, and where is it located on my 88. Is it one of the two right behind the battery??
Any info would be appreciated.
Bob
Do I suspect the relay, and where is it located on my 88. Is it one of the two right behind the battery??
Any info would be appreciated.
Bob
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Fuel pump not running (Bob88Convertible)
You can see if power is getting through the fuse and relay by connecting a test light or DMM between ALDL connector pins A (upper right) and G (lower left).
If power is getting to that pin, you might want to clean the three contact points under the fuel pump mounting flange before replacing the fuel pump. These pins become blackened with oxide over time and can cause the fuel pump to not operate.
If power is getting to that pin, you might want to clean the three contact points under the fuel pump mounting flange before replacing the fuel pump. These pins become blackened with oxide over time and can cause the fuel pump to not operate.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Fuel pump not running (Bob88Convertible)
Check the fuel pump fuse with an ohmeter and look at the fuse clip contacts for no corrosion. Jump 12v on either side of the fuel pump fuse (fuse in place) to confirm that the fuel pump is ok. See if 12v is on the green/wh wire on the fuel pump relay in the crank position (ECM applies 12v there to make the pump run). Measure for ground connection with an ohmeter on the black/wh wire on the fuel pump.
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 1,036
Likes: 0
From: Plant City Fl
Re: Fuel pump not running (65Z01)
You can see if power is getting through the fuse and relay by connecting a test light or DMM between ALDL connector pins A (upper right) and G (lower left).
If power is getting to that pin, you might want to clean the three contact points under the fuel pump mounting flange before replacing the fuel pump. These pins become blackened with oxide over time and can cause the fuel pump to not operate.
If power is getting to that pin, you might want to clean the three contact points under the fuel pump mounting flange before replacing the fuel pump. These pins become blackened with oxide over time and can cause the fuel pump to not operate.
No power on pins A and G. That mean relay??? Can't find fuse, not in fuse panel. :(
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 1,036
Likes: 0
From: Plant City Fl
Re: Fuel pump not running (jfb)
Did'nt find the fuse yet, but to complicate things, it started. WTF I hate these kind of problems, would be much easier if something was just broken. :mad Any other ideas. Thanks for the help.
Bob
Bob
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Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
Re: Fuel pump not running (Bob88Convertible)
All connections supplying power to the fuel pump need to be bright and tight, so there are a number of push on connectors that can be intermittent and cause your symptoms. The connector at the fuel pump is out in the elements and has the best chance of oxidizing. I would at least spray that connection with contact cleaner.
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Re: Fuel pump not running (Bob88Convertible)
The fuel pump fuse is a 10A fuse labeled FP located in the lower right corner of the fuse block.
During cranking the ECM supplies power to the fuel pump through the FP relay; after the engine starts power is only supplied through the oil pressure switch which is located atop the block behind the intake base to the left of the dist.
If the trouble should return you can apply power to the fuel pump for testing by jumpering a source of +12Vdc to pin G of the ALDL.
During cranking the ECM supplies power to the fuel pump through the FP relay; after the engine starts power is only supplied through the oil pressure switch which is located atop the block behind the intake base to the left of the dist.
If the trouble should return you can apply power to the fuel pump for testing by jumpering a source of +12Vdc to pin G of the ALDL.
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 1,036
Likes: 0
From: Plant City Fl
Re: Fuel pump not running (65Z01)
Found a fuse in the lower right of the fuse panel marked FR?? Fuel relay maybe?? Also jfb suggested cleaning the connector at the fuel pump. Is that under the fuel door?? Thanks again for all the help.
Bob
Bob
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Fuel pump not running (Bob88Convertible)
The connections that get a black oxide coating over time are just under the fuel pump mounting flange.
To access there you must remove the fuel door, the rubber boot, the three fuel lines, the circle of bolts and disconnect the electrical connection. Then just lift the fuel pump assembly carefully from the tank.
To access there you must remove the fuel door, the rubber boot, the three fuel lines, the circle of bolts and disconnect the electrical connection. Then just lift the fuel pump assembly carefully from the tank.
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 1,036
Likes: 0
From: Plant City Fl
Re: Fuel pump not running (Bob88Convertible)
Follow up. As I said last week, after checking a few things, but not actually doing anything the car started. :mad
I don't drive during the week, so the car was idle in the garage. Went out this morning to start it and no fuel again.
Took the rubber boot off under the fuel door and unplugged the electrical connection. Plugged it back in and it started. WTF. Should I go ahead and pull the pump out. Is there some other way to check and see if it is good??
Does it sound like just a bad connection??
Thanks again for any info.
Bob
I don't drive during the week, so the car was idle in the garage. Went out this morning to start it and no fuel again.
Took the rubber boot off under the fuel door and unplugged the electrical connection. Plugged it back in and it started. WTF. Should I go ahead and pull the pump out. Is there some other way to check and see if it is good??
Does it sound like just a bad connection??
Thanks again for any info.
Bob
