F9T DME relay

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03-11-2020, 07:32 PM

#16

MarinS4

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Quote:

Originally Posted by Meenrod

I just checked on my '96 OBD2 993- fuel pump primes for a few seconds with ignition in on position. Standard relay.

Very strange.

Mine too. 96 C4S with 97 ECU.

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05-14-2021, 04:06 PM

#17

Jbelt01

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Quote:

Originally Posted by Spokayman

Yesterday I switched out the F9 pump-prime relay from my ‘95 968 to my ‘95 Carrera, and I can confirm that it does indeed run the pump for several seconds when the ignition key is switched to the “on” position.
The pump does not run (on either car) with a standard relay, but does run on both cars with the pump-prime relay.

like others I bought the solid state relay a couple years ago because it seemed likely to be the most trouble free option, and I figured the pump-prime function was an interesting feature and a potential benefit for quicker starting.

I installed a F9 solid state pump-prime relay today in my 97’ 993. With the car off and key removed, the fuel pump turned on and ran for 30-45 seconds until I pulled the relay to shut it down.

I installed the original relay and everything was quiet. No running pump. I was able to star the car without issues.

I have no idea why the F9 solid state relay would immediately energize the fuel pump with the key removed. Very odd. I’ve asked to swap it out with the non pump-prime version.

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05-14-2021, 04:46 PM

#18

FLPhil

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I had a similar issue, waiting on a replacement from F9. In addition to running the pump the new relay also became warm to the touch.

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05-14-2021, 05:37 PM

#19

notabot

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Quote:

Originally Posted by FLPhil

I had a similar issue, waiting on a replacement from F9. In addition to running the pump the new relay also became warm to the touch.

The latter is normal.

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05-15-2021, 01:35 AM

#20

FLYT993

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been running mine for a few years now; peace of mind from the DME gremlins.

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05-15-2021, 01:50 PM

#21

ed devinney

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Quote:

Originally Posted by FLYT993

been running mine for a few years now; peace of mind from the DME gremlins.

I still carry a spare

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05-17-2021, 12:10 AM

#22

Peteinjp

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You can always just jump the terminals if needed. Just have to pull the jumpers each time you stop the car.

Pete

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05-17-2021, 06:06 AM

#23

chartwell

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DME Relay

I don't know if this is related but after installing the F9 DME relay and starting the engine to ensure all was well , a few days later the battery had gone totally flat. I since recharged it but was wondering if I should swap out the new for old relay? Any thoughts?