Fuel Pump diagnostics?
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Fuel Pump diagnostics?
Here's what I got. Just purchased this 1986 Vette that's been sitting a few months. Prior to purchasing it I started it a few times and it started fine. The day I picked it up I take it across the street to see if it would smog. I left it there. The mechanic left it running for a long time, I assumed to let the cat heat up. After awhile it dies. He thinks it ran out of gas. I put in 8 gallons. It cranks but does not start. Checking pressure at the fuel rail it seems there is none. I don't hear the fuel pump. Could it be a relay, a fuse, the pump itself? Will the pump go bad by running out of gas? Where do I start to diagnostic this? Where/is there, a relay or a fuse. Where do I check to see if the pump is getting power? Any help is greatly appreciated. Thanks.
Le Mans Master
Joined: Aug 2000
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From: Australia
If pump runs then check relay mounted on firewall
Last edited by rodj; Mar 9, 2010 at 09:18 PM.
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Thank you so much! I will do that. Just a couple of questions. Which fuse runs the pump? On the fuse panel on the passenger side of the dash I don't see one labeled "fuel pump". Is it called something else? Which relay on the firewall is it? Thank you again.
Team Owner
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From: Summerland B.C. Canada
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you know the fuel pump comes out through the fuel door. Pull the door off and there is a rubber boot covering a flange with about a dz 10mm bolts. Get them out and the whole fuel sender and pump come out. When mine was changed the guy had never seen a corvette before and had it done in less than a 1/2 hour. If I knew it was that easy I would have done it in the parking lot myself.
JS
JS
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you know the fuel pump comes out through the fuel door. Pull the door off and there is a rubber boot covering a flange with about a dz 10mm bolts. Get them out and the whole fuel sender and pump come out. When mine was changed the guy had never seen a corvette before and had it done in less than a 1/2 hour. If I knew it was that easy I would have done it in the parking lot myself.
JS
JS
Le Mans Master
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From: Australia
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From: Palm Bay Florida
Le Mans Master
Joined: Aug 2000
Posts: 8,838
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From: Australia
Team Owner
Joined: Jan 2003
Posts: 20,298
Likes: 240
From: Summerland B.C. Canada
The rear one is should to be the fuel pump relay, but someone could have changed that arrangement. Does the overdrive work ?
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Thanks! It RUNS!
Thank you for the detailed instructions guys! Ok, checked the fuse. It was good except the diagram looks like it's labeled "FP" but mine was labeled "FR" (fuel relay?). Ran a 12v jumper to pole "G" on the ALCL. I could here something clicking (the relay) but did not hear the fuel pump running. Went to Autozone and got a fuel pump. Pulled the old one (it had been replaced before. One of the tack welds on a bracket broke and it was wired together now. Changed the fuel pump. Start car and PRESTO! Car runs.
So I got to drive it for the first time. Motor is strong but needs a tune up. Going through the gears good solid shift into second, going into third......nothing. Like going into neutral. Guess it's tranny time.
So I got to drive it for the first time. Motor is strong but needs a tune up. Going through the gears good solid shift into second, going into third......nothing. Like going into neutral. Guess it's tranny time.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
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From: Australia
Will it hook 4th?
If the shifter and linkages are working properly it might have broken the comb of the shaft that moves the selectors inside the trans.They are only pressed on and come adrift
Parts # 69 and 70 in link below
http://www.tbtrans.com/t10_transmission.htm#t10_pics
Easy fix by removing side cover on trans and replacing.
Gearbox part of 4+3 trans is a regular BW Super T10
If the shifter and linkages are working properly it might have broken the comb of the shaft that moves the selectors inside the trans.They are only pressed on and come adrift
Parts # 69 and 70 in link below
http://www.tbtrans.com/t10_transmission.htm#t10_pics
Easy fix by removing side cover on trans and replacing.
Gearbox part of 4+3 trans is a regular BW Super T10
