F9T DME relay
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Drifting
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From: New Jersey
F9T DME relay
I was looking to replace my DME/fuel pump relay with the solid state version from F9T. Noticed they have two versions available (standard and pump-prime).
As the name implies, the latter runs the fuel pump for a few seconds at the “on” position (or presumably a split second earlier as you rapidly turn the key). It advertises smoother starts as a result.
Curious on consensus from those that have purchased the solid state DME relay?
As the name implies, the latter runs the fuel pump for a few seconds at the “on” position (or presumably a split second earlier as you rapidly turn the key). It advertises smoother starts as a result.
Curious on consensus from those that have purchased the solid state DME relay?
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Seared
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Drifting
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From: New Jersey
Thanks guys. I was thinking the same thing... "is this fixing a problem that doesn't exist?" but then inline with some others figured it may come in handy to have that feature. It's only an extra $8.
Just wanted to see if anyone had any reasons why this would be a bad idea (can't think of one).
Just wanted to see if anyone had any reasons why this would be a bad idea (can't think of one).
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From: Dallas, TX
Am I missing something, I have the original relay and sometimes I hear the pump run for a moment when I turn the ignition on but have not turned it to the start position. Is this what is being referred to as a priming function above? I would think the running of the pump relates to some sort of pressure sensor on the high side of the pump.
Andy
Andy
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Hi Andy,
With the stock DME relay, the fuel pump isn't powered up until the engine is cranked over by the starter a certain number of times (30?). I never heard the pump run with the stock relay--other noise obscures it.
The "pump prime" feature on this version of the F9T relay powers up the fuel pump when the key is turned to the "on" position, before the engine is cranked over, for about three seconds, and then turns it back off. This is a way to check periodically that all is good, hear the fuel pump run, and then hear it stop (a safety function--the pump should not run unless the engine is also running).
None of this is required on the 993, it's just a little extra for those of us in the Belt and Suspenders Club...
With the stock DME relay, the fuel pump isn't powered up until the engine is cranked over by the starter a certain number of times (30?). I never heard the pump run with the stock relay--other noise obscures it.
The "pump prime" feature on this version of the F9T relay powers up the fuel pump when the key is turned to the "on" position, before the engine is cranked over, for about three seconds, and then turns it back off. This is a way to check periodically that all is good, hear the fuel pump run, and then hear it stop (a safety function--the pump should not run unless the engine is also running).
None of this is required on the 993, it's just a little extra for those of us in the Belt and Suspenders Club...
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I purchased a non priming relay in 2017 shortly after buying my 964 Cab. I felt it improved starting over the stock relay. Always wondered about the priming feature and recently bought priming version and installed. I can hear the pump run for a couple of seconds as soon as I turn the key, haven't noticed any major difference between either version in starting or driveablity since installing the priming relay. No complainants about either one.
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From: Southern Arizona
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.
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.