EFI main relay keeps going out (1 Viewer)

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Where are you buying it from? I’ve had really bad luck with Autozone ones. Although, even those would last 6 months or so. Might try a better quality one, but likely there’s an underlying issue. I couldn’t help, in that regard.
 
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You might try pulling the fuse block that the EFI relay plugs into, to check the connector and wires underneath it. Check the connector, and wires that feed that relay for corrosion, or signs of them melting.
 
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You might try pulling the fuse block that the EFI relay plugs into, to check the connector and wires underneath it. Check the connector, and wires that feed that relay for corrosion, or signs of them melting.
Good advice. Planning to do that this weekend. I’ve heard somewhere those wires may have been a little too small from factory. Planning to check grounding as well. Just upgraded battery wires and terminals.
 
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I don't know what it is about that EFI relay, but the one in my truck always runs HOT! I don't mean a little hot, but VERY HOT! To the point that after my trucks been running for only a few minutes, you can't even hold on to that relay with your bare fingers for even a few seconds.
 

baldilocks

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If the connections in the relay box are good with no sign of old and crusty wires, replace the EFI relay with part number 28300-16010. It is a drop in replacement from a Toyota Camry starter circuit.
A search show that the relay you suggested is quite a bit more expensive than the original part. You must have suggested it for a good reason. Could it have more heavy duty internals?
 
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^^^---Don't do this. The factory spec fusible links are up to the task. Replacing it with a higher amperage link or, worse yet, just a wire, is asking for a fire or some other downstream damage. Fix the root of the problem. If the fuse or relay wires on the bottom of the fuse box look toasty, then order some new pigtails from Toyota and upgrade the wiring to 10 AWG. If the wires look unburned and clean, upgrade the relay to the plastic one Jon mentioned. It tends to not get as hot as the OEM metal one.
 
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The relay wire to the fuse box is the fusible link im talking about.I use the OEM relay and it dosent get hot, and the amperage is the same i measurered it its been nearly a decade so i have that as proof while you just speculate.
 
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^^^---Don't do this. The factory spec fusible links are up to the task. Replacing it with a higher amperage link or, worse yet, just a wire, is asking for a fire or some other downstream damage. Fix the root of the problem. If the fuse or relay wires on the bottom of the fuse box look toasty, then order some new pigtails from Toyota and upgrade the wiring to 10 AWG. If the wires look unburned and clean, upgrade the relay to the plastic one Jon mentioned. It tends to not get as hot as the OEM metal one.
20210507_194446.jpg
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20210507_194548.jpg

Daily driven with 315,000 miles and 7 years since I replaced it, this is what it looks like as i type this. Where is the fire?
 
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The only fusible links in the cruiser are the ones at the battery in the little plastic box. If you just replaced the wire between the relay and fuse, that's good. It's a tried and true upgrade for this problem.
 
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The relay wire to the fuse box is the fusible link im talking about.I use the OEM relay and it dosent get hot, and the amperage is the same i measurered it its been nearly a decade so i have that as proof while you just speculate.
Then you didn't change a fusible link. You changed a wire. 2 very different things.
 
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A search show that the relay you suggested is quite a bit more expensive than the original part. You must have suggested it for a good reason. Could it have more heavy duty internals?
I never took one apart, so I really don't know. However I did use it in my 91 for a good 15 years or so.

Keep in mind that Toyota used the same relay in the same location for all US spec 80s from 91 to 97.
The 3FE has an issue due to the location of the exhaust manifold, which is right under the relay box. The 1FZ manifold is on the opposite side.
The combination of heat and time will eventually degrade things.
For whatever reason, the Camry relay seems to be a bit more resilient.
I had rewired the EFI circuit many years ago from the EFI fuse, relay, to connector EB1 with high temp wire using all OEM connectors. The new relay was my final step in making the system bullitproof.
 
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A search show that the relay you suggested is quite a bit more expensive than the original part. You must have suggested it for a good reason. Could it have more heavy duty internals?

Did this on my 91. If I would stop at a convenience store or something, I couldn't start my engine when the relay was hot. I used to pull the relay, walk into the store, and hold it in the freezer to cool it down enough to start up again. Swapped to the Camry relay and haven't had an issue in over 4 years.
 

baldilocks

Battle Ground, WA
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Did this on my 91. If I would stop at a convenience store or something, I couldn't start my engine when the relay was hot. I used to pull the relay, walk into the store, and hold it in the freezer to cool it down enough to start up again. Swapped to the Camry relay and haven't had an issue in over 4 years.
I remember this being discussed in years past and iirc, this problem was with the 3fe. I have a 1993 with 305k miles and have never experience a problem with the efi relay.
 

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