Auto mechanic advice needed please.

jeffro503
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St Helens, OR US
12/16/2015 2:23pm Edited Date/Time 12/17/2015 1:54pm
Hey guys....I have a 99' Chevy , extended 1 ton cargo van as my motovan. I've been having an issue with the " fuel relay fuse / switch ". It the little 1" X 1" black fuse and for some reason keeps losing connectivity. It just randomly dies on me every once in a while. Sometimes I can start it right back up , and other times I have to pop the hood , wiggle the relay switch ( which is super tight ) and it'll fire back up again.

It's been an on-going issue that I haven't had any luck in getting it fixed. My mechanic has been an authorized Chevy mechanic with just about every certificate known to man and I trust him. And he can't get any info at all when he plugs in the little computer box thing to see what it's doing.

The old relay switch I pulled out , had the plastic slightly melted around one of the pins. Which tells me that , that specific pin is losing connectivity. The new one I put in there has no melted areas , but is still losing connectivity.

About the only thing I can think of doing next is replacing the entire fuse panel. BUT.....what if that isn't what it is? What if one of the wires leading to the fuse box , shorting out or something like that?

FWIW....I'm going from memory here , but I think I got the fuel pump replaced about a month or so before I started having this issue. Could the fuel pump be causing a short some where?

Just wo9ndering if this is something I could get some advice on , or maybe brain storm some possible reason's as to why it's happening. When that big cargo van loses power....it doesn't want to stop or steer worth a shit. And I'm worried about wrecking it or hurting someone else.
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MR. X
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North Tonawanda, NY US
12/16/2015 2:54pm
Isnt there a couple other relays right next to it that are the same part number ? Did you try just replacing the relay?
GIwasB4
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Beverly Hills, CA US
12/16/2015 4:40pm
OEM or aftermarket fuel pump?
tah duh! The answer to this question is the answer to your question

The Shop

Old-Man
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Colorado springs, CO US
12/16/2015 4:56pm Edited Date/Time 12/16/2015 5:32pm
MR. X wrote:
Isnt there a couple other relays right next to it that are the same part number ? Did you try just replacing the relay?
Think thats what he mentions here "The old relay switch I pulled out , had the plastic slightly melted around one of the pins"
Your mechanic couldn't figure this out without a puter? or is that all he does, fix things that the puter pulls up? Just asking man no harm here. did he ask the Old timers their at his shop? bet they have come across this situation before.

If the relay that is having the problem is directly in current with the fuel pump and you never had a problem till you recently put a new one in then I would start with that.

Look up the new pump #'s already installed and see if the Local chevy dealer uses the same or if there is a compatibility issue.

Had a similar relay problem on a 08' Mustang it turned out to be the temp plug in the block not the relay

But your's may be a different animal in regards to the new pump.. I would think that the fuse under the dash would blow before the relay going bad but who know if the relay wasn't going bad before the relay was anyway?

Had a 98' Chevy where if you had anything in the cigarette lighter it would blow the fuses and that same fuse was in current with the fuel pump... look for any BS in the cig lighter too.

Which by all your posts it's probably some sort of joint holding metal...Smile just kiddin man!
Hope you get it figured out
Sandberm
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Pasco, WA US
12/16/2015 5:17pm
Aren't chevy in-tank fuel pumps famous for going out? The one in my 03s-10 did. So did the one in my dads 02 1/2 ton. Neighbors suburban too.Huh

I heard....when the fuel level gets below the working part of the pump, the pump loses the gases cooling effect and gets hot and stops working. You stop, get out and pop the hood, wiggle some shit and in the mean time the pump cools down and then when you hop back in the rig it fires up. You think it was because you wiggled the relay but it was actually the time the pump had to cool down.

Solution: never let your chevy get below half a tank full. All anecdotal second hand info of course.Pinch
500guy
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AZ US
12/16/2015 6:38pm
You can pull an amperage draw on the pump to determine if it is overloading the relay, I have no experience with this Van but I do know that the connections in those power distribution boxes do go bad and cause this melting issue.
jeffro503
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St Helens, OR US
12/16/2015 6:41pm
As far as the pump being OEM , I'm pretty sure it is. If asked , I always go with OEM because they just seem to last longer. I am going to their shop on Saturday for a Christmas party they invited me too. I'll ask him if it was indeed a OEM pump. I can't be sure , but to me it sounds like something on that newer pump is what's giving me issues. I only owned the van about two months before the fuel pump went out , but even with a failing pump , it never randomly died on me while driving. Now it does. The guy who worked on it also owns the shop. Her's an extremely honest dude that is very well known here in town. I'll have a heart to heart with him on Saturday about it. Because the bottom line is , I need that van reliable.

Thanks for your input so far guys. OH....and I'll check out the cigarette lighter as well. I've never used it , so I'm not even sure it works.
jeffro503
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St Helens, OR US
12/16/2015 6:42pm Edited Date/Time 12/16/2015 6:45pm
Sandberm wrote:
Aren't chevy in-tank fuel pumps famous for going out? The one in my 03s-10 did. So did the one in my dads 02 1/2 ton. Neighbors...
Aren't chevy in-tank fuel pumps famous for going out? The one in my 03s-10 did. So did the one in my dads 02 1/2 ton. Neighbors suburban too.Huh

I heard....when the fuel level gets below the working part of the pump, the pump loses the gases cooling effect and gets hot and stops working. You stop, get out and pop the hood, wiggle some shit and in the mean time the pump cools down and then when you hop back in the rig it fires up. You think it was because you wiggled the relay but it was actually the time the pump had to cool down.

Solution: never let your chevy get below half a tank full. All anecdotal second hand info of course.Pinch
yes....the pump is in the tank. same as on my fords.

And I usually keep that thing pretty full. very rarely I let it get below 1/2 tank because of all the driving to the tracks is usually at least 45min to 2hrs away. It should NOT be doing that though. No reason for a rig to die unless she's pretty low on fuel. And I've treated the hell out of the fuel with some of the Lucas oil stuff.
jeffro503
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St Helens, OR US
12/16/2015 6:42pm
500guy wrote:
You can pull an amperage draw on the pump to determine if it is overloading the relay, I have no experience with this Van but I...
You can pull an amperage draw on the pump to determine if it is overloading the relay, I have no experience with this Van but I do know that the connections in those power distribution boxes do go bad and cause this melting issue.
That's a great idea Jay. I will ask him to do that as well.
CR250Rider
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Moses Lake, WA US
12/16/2015 7:22pm
Sandberm wrote:
Aren't chevy in-tank fuel pumps famous for going out? The one in my 03s-10 did. So did the one in my dads 02 1/2 ton. Neighbors...
Aren't chevy in-tank fuel pumps famous for going out? The one in my 03s-10 did. So did the one in my dads 02 1/2 ton. Neighbors suburban too.Huh

I heard....when the fuel level gets below the working part of the pump, the pump loses the gases cooling effect and gets hot and stops working. You stop, get out and pop the hood, wiggle some shit and in the mean time the pump cools down and then when you hop back in the rig it fires up. You think it was because you wiggled the relay but it was actually the time the pump had to cool down.

Solution: never let your chevy get below half a tank full. All anecdotal second hand info of course.Pinch
Great advice for sure. I had a Blazer that the pump quit in. When I pulled it out there was a ton of corrosion around it like a corroded battery almost. Cheap gas can aggravate that problem I believe.

Hey Jeffro, couldn't you put an amp meter on the pump circuit and see if it's drawing the normal amps?
Could be intermittent too I guess. Hard to diagnose that.
If I had to speculate, I'd say the positive wire might have insulation wore off somewhere and is grounding out a bit.

That's a tough one, goodluck bud
tomm55x
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Erie, PA US
12/17/2015 3:42am
Unbolt your fuse/relay box and flip it upside down and look to see if the wiring in the bottom going to your fuses and relays are corroded and cooked, if so replace the current box with a used one.
Knoby
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Wichita, KS US
12/17/2015 3:55am
I'm seriously not trying to be a dick here but trade in your mechanic for a technician. Wiring \ Electrical problems are very very easy to fix.
hillbilly
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Afton, TN US
12/17/2015 6:44am
I'd pull the tank and put in a pump,seen many short out and burn things far from the pump because of the amp drain. If there is a bad connection in the line it will heat it up.
vet323
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Lead, SD US
12/17/2015 6:48am
tomm55x wrote:
Unbolt your fuse/relay box and flip it upside down and look to see if the wiring in the bottom going to your fuses and relays are...
Unbolt your fuse/relay box and flip it upside down and look to see if the wiring in the bottom going to your fuses and relays are corroded and cooked, if so replace the current box with a used one.
This likely what you'll find. Wiring could have been damaged by a poor connection at the relay (not uncommon). There is a circuit protection fuse for this circuit, but because of where it is in the circuit, a poor relay connection may not cause it to blow.
809
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Paducah, KY US
12/17/2015 8:41am
tomm55x wrote:
Unbolt your fuse/relay box and flip it upside down and look to see if the wiring in the bottom going to your fuses and relays are...
Unbolt your fuse/relay box and flip it upside down and look to see if the wiring in the bottom going to your fuses and relays are corroded and cooked, if so replace the current box with a used one.
vet323 wrote:
This likely what you'll find. Wiring could have been damaged by a poor connection at the relay (not uncommon). There is a circuit protection fuse for...
This likely what you'll find. Wiring could have been damaged by a poor connection at the relay (not uncommon). There is a circuit protection fuse for this circuit, but because of where it is in the circuit, a poor relay connection may not cause it to blow.
If you do this and you don't see corrosion but it looks like it has been hot, check the amperage the pump is pulling. I have seen this one other time where there was a restriction in the fuel line caused the pump to pull more amps than normal. It didn't blow the fuse but did overheat the relay.
jeffro503
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St Helens, OR US
12/17/2015 1:54pm
Some really good info in here guys. Thanks again. Just trying to get this thing 100% road worthy for this next spring / summer.....lots of riding planned.

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