Re: Landcruiser fuel injection relay problem

Scott wrote:
I have revisited the possibility of corrosion on the terminal ends of
the relay and in the sockets. There doesn't appear to be any actual
obvious corrosion but one of the 4 terminal ends is somewhat
discolored. I now believe they are all originally brass but one of
them looks somewhat like it is copper. What I mean is that I think
possibly one is heat-discolored or perhaps oxidized in an odd manner.
I remember now noticing this awhile back but thinking it was just a
differnet alloy like hot side connections on 120v plugs, etc. All 4
socket holes look fine and the same. This relay is in an enclosed box
under the hood and it looks like new inside the box. All 4 socket
holes look identical and normal. What is odd is there is never any
cold failure of the relay. They always work if left to cool down and
never fail while running regardless of how hot things are. Do these
things only operate at start-up?

In any event I treated all the terminals and the socket with A-120
Corrosion Free. A-120 is basically a penetrant/lubricant/moisture
displacer with a high dielectric strength sold in some marine stores
to treat fuse boxes, etc. in damp high corrosion environments. It is
hard to find but good stuff and comes, or did come in an aerosol can
that has a yellow label that looks straight out of the 1940's. So far
no start-up failures but it has been a bit cooler and I haven't given
it a real test yet with a few quick stops after a real warm-up.

I think most probably the discoloration is a symptom of the problem
and not the cause but I don't know. Any more thoughts now that I am
giving more complete information? After talking to the parts guy at
Toyota I am pretty sure that new relays have identically colored
terminals, at least now they do. However all three of my rotating
relays have a discolored terminal. I should have been paying more
attention to this before but it is hell to get old and need reader
glasses for close-up vision but not use them when driving.

Scott

Can you visually check the wire ends under the socket terminal to be sure that they are not frayed (perhaps an intermittent short) or breaking? Sometimes wires will fail where they are crimped or connected to the socket terminals themselves that are then inserted into the plastic relay socket if it was made that way. Some are sealed and just a harness is visible.

If I understood correctly, you did mention earlier that the check engine light does not illuminate when you know it's not going to start when you turn the key. That in itself may have set a trouble code in the computer. If you have not had it scanned, that may be another possibility. You can sometimes have it scanned free at parts stores.

I took the time to look at a mid nineties land cruiser schematic and it may not be exactly like yours, but on that one, the EFI relay as well as the check engine light is powered through the ignition switch (perhaps a clue) and controls / powers the circuit opening relay that controls the fuel pump.

The ignition switch is a possibility but needs to be tested when the problem occurs with a voltmeter to check power to the relay. The check engine light will probably be out. The fuel pump is a remote possibility. Check all grounds for corrosion and clean as necessary. That in itself is a very neglected cause for problems.

Follow your wiring diagram and check to see if those components are common.
.

Relevant Pages

  • Re: Landcruiser fuel injection relay problem
    ... obvious corrosion but one of the 4 terminal ends is somewhat ... socket holes look fine and the same. ... This relay is in an enclosed box ... In any event I treated all the terminals and the socket with A-120 ...
    (alt.autos.toyota)
  • Re: Landcruiser fuel injection relay problem
    ... socket holes look fine and the same. ... This relay is in an enclosed box ... Corrosion Free. ... terminals, ...
    (alt.autos.toyota)
  • Re: Landcruiser fuel injection relay problem
    ... socket holes look fine and the same. ... This relay is in an enclosed box ... In any event I treated all the terminals and the socket with A-120 ... Corrosion Free. ...
    (alt.autos.toyota)
  • Re: Landcruiser fuel injection relay problem
    ... socket holes look fine and the same. ... This relay is in an enclosed box ... Corrosion Free. ... terminals, ...
    (alt.autos.toyota)
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    ... My wifes VAIO has an unreliable PSU socket, ... I reckon I can fit the socket I have and it fits the PSU ... terminals, ... terminal B when no plug is in the socket, but when the plug is inserted, ...
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