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Subject:Re: Digifant II quirky issue. 3000 RPM rev limit?
From:Neil N
Date:Thu, 11 May 2017 10:16:49 -0700

this is a LONG SHOT idea but most relays of this type have a diode or
resistor or similar in parallel on switch side of relay. I REALLY
doubt this comes into play here, but is polarity on switch side
important in this application?

If i recall, Vanagon relays typically use 85 for ground, 86 for positive.

Image of a Vanagon relay showing part I refer to:

https://goo.gl/photos/tzx1TGCW8TFCZ2J2A

and image showing where intermittent fault happened at my FP relay (Jetta part)

https://goo.gl/photos/YoANC3d3HgxAhphJ9

On 5/11/17, Chris S <szpejankowski@gmail.com> wrote:
> When I bypassed the fuel pump relay it revs to the redline.  Since the
> problem started after I replaced the relay, we may have found the issue. I
> will order another relay and cross fingers.
>
> Thanks, Alex!
>
> Chris
>
> Dnia 11.05.2017 o godz. 12:05 Alex Towner <alexandertowner@GMAIL.COM>
> napisał(a):
>
>> I hope I'm not covering this again, since I get the list in digest form.
>>
>> My amateur garage would be removing the fuel pump relay and installing a
>> jumper wire between terminals 87 and 30 (the perpendicular center ones).
>> Keep in mind this will run the fuel pump from the second it is installed
>> and should only be inserted when you are planning to run the engine.
>> Remove
>> it when the engine is off to prevent battery drain and flooding.
>>
>> By removing the relay and replacing with a jumper the relay is removed as
>> a
>> potential cause of your woes.
>>
>> It is possible for a VW fuel pump relay to limit RPM. Not sure how it
>> works, but certain CIS injected Golfs and Foxes circa '85 - '87 had a FP
>> relay that cut off the fun at 6000 RPM. You could have a defective one of
>> those installed or some sort of industrial engine one perhaps?
>>
>> I think looking at the distributor next as you have been doing makes
>> sense.
>>
>> Hope this helps.
>>
>> Alex
>

-- 
Neil n

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