Cold start issues

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jaxmr2
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Cold start issues

Post by jaxmr2 » 17/09/17 18:11

Hi guys.

After many years of trouble-free MR2-ing, my beloved Rev3 GLtd is refusing to start from cold. :crybaby: :w_tf:
It will fire up with starter fluid, although takes a few goes and it definitely isn't getting fuel from cold, as it dies, once the starter fluid has bern used up.
After a few goes and once it will rev, the fuel rail must kick in, as it runs fine, will rev cleanly and ticks over as it should.
I've read somewhere there's a relay which tells the fuel pump to prime/run even though engine isn't running.......is this correct and if so, where is it ?
If there isn't such a relay, what else could be the issue ? :confused1:
Hope you can help.
Jax

jaxmr2
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Re: Cold start issues

Post by jaxmr2 » 19/09/17 13:53

Anyone ?

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Gazza_DJ
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Re: Cold start issues

Post by Gazza_DJ » 19/09/17 14:05

Try bridging B+ and FP in the diag port. This bypasses the fuel pump relay. If it works you know it's problem related to the relay or the circuit that energises the relay, resistor pack, fuses.
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abovetherim
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Re: Cold start issues

Post by abovetherim » 19/09/17 21:51

Could be the ect (engine coolant temperature) sensor is kaput. you can test the resistance of it over temp range and compare to the toyota chart in the BGB. The ECU takes a reading off the ect to help it decide how much fuel to throw in there
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jaxmr2
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Re: Cold start issues

Post by jaxmr2 » 20/09/17 19:45

Thanks

Will give them a try and report back.

Am I right in thinking the n/a engine doesn't have a cold start injector and timer switch ?

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abovetherim
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Re: Cold start issues

Post by abovetherim » 20/09/17 21:19

Not sure about rev 3 but if you look at the coolant tree where the ect is plugged in (IIRC green connector) there will be a grey plug the same plugged into the cold timer start switch if there is one.
Another thing to look at is the idle air control valve could be not closing properly as they can gum up with time
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Torero
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Re: Cold start issues

Post by Torero » 21/09/17 10:20

Gazza_DJ wrote:
19/09/17 14:05
Try bridging B+ and FP in the diag port. This bypasses the fuel pump relay. If it works you know it's problem related to the relay or the circuit that energises the relay, resistor pack, fuses.
This :th:

Definitely where I'd start, purely so you can confirm/eliminate one major cause.

Always helps to establish facts when analysing an issue, then you can move on to assessing the unknown.

Keep us posted and good luck, hopefully it's something basic.

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