924Board.org

Lizard · Posted: Sat Feb 14, 2004 11:35 am Post subject:

hmm, with a switch in the 80 931 that I had there was NO rev limiter
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3 928s,

Smoothie · Posted: Sun Feb 15, 2004 1:01 am Post subject:

Due to a preponderance of evidence in support of it, I think it's safe to say the jury has reached a verdict and finds beyond a reasonable doubt that there is indeed a rev limiter contained within said fuel pump relay 931.615.113.00.

Don't mind me. Jury duty last Monday's got me talking legalezze. The trial of Jayson Williams happened to be going on at the same court where I had to report (Somerville, NJ). All the news trucks were there - ABC-6 Phila., ABC-7 NY, CBS-2 NY, NBC-4 NY, Fox-5 NY, Channel 12 and a Village something-or-other that I never heard of. Apparently Court TV is there too, but I didn't see a truck for them - maybe they're with that Village truck. It warmed my heart to see them all parked in a row with satellite antennae pointed to the sky and cameras on tripods pointed at the building, but they were all on completely the wrong side of the building to catch Williams entering or leaving.

Court TV will be airing the festivities when the trial resumes on Tuesday.
For anyone who doesn't know, he's the former NJ Nets basketball player who much like a lottery winner, struck it filthy rich and now seems to be in the process of throwing it all away. Apparently he's done some good stuff with charities and the like, but on the other hand he's shot a security van, almost shot the head off a pro football player buddy, shot his own dog to death after loosing a bet, then graduated to shooting and killing his chauffer. He's on trial for the death of the chauffer.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

Lizard · Posted: Sun Feb 15, 2004 1:06 am Post subject:

Hey smoothie, he sounds like a real winner
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3 928s,

mick · Joined: 13 Jun 2003 Posts: 183 Location: ohio

i was just getting ready to ask about the relay issue i bought the rabbit/924 one last may and it crapped out already so i grabbed an original of the only 931 in the junk yard and it works fine . but i can hear a fuel pump making noises kind of a grinding type noise. is it correct that there is one in the tank and one on the frame?i got the frame one at the yard along with a used accumulator. the acc. works fine but im scared to replace the pump because i cant hear where the noise is actually coming from.
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80 931 intercooled,1 bar, and kinda runs right

Smoothie · Posted: Sun Feb 15, 2004 1:42 pm Post subject:

Do you remember if that was a 477. relay? -or a 433. that burnt out? I'd guess a 477.
Yes you'll have 2 pumps - an in-tank and an external.
The external pump normally makes a buzzing sound. There are steel rollers being spun around inside it, so that's the kind of sound. It's normally loud enough to hear even from the drivers seat.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

mick · Joined: 13 Jun 2003 Posts: 183 Location: ohio

the receipt says 433 906 05. as the pumps go it can only be heard from the back of the car so i guess thats normal i just dont remeber ever hearing it before thanks..
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80 931 intercooled,1 bar, and kinda runs right

mick · Joined: 13 Jun 2003 Posts: 183 Location: ohio

also for anybody needing another relay there a place in columbus called pap-parts that sells them for 60.00$. the best ive found.
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80 931 intercooled,1 bar, and kinda runs right

Smoothie · Posted: Mon Feb 16, 2004 1:58 am Post subject:

Here's a recording of my fuel pump sound -
http://www.geocities.com/Smoothies931Sounds/Trk02-15sec-48kHz16bitStereo.mp3
The stereo mic (actually headphones plugged into the mic jack) was placed outside at the back of the car, so the sound of the pump is louder than you'd normally hear it. First the key gets turned part way to activate the pump, then the engine is started and you hear the engine, fuel pump/s and possibly a little exhaust rattle. It's 15 seconds long and about 240 KB.
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

mick · Joined: 13 Jun 2003 Posts: 183 Location: ohio

thanks smoothie! thats what mine sounds like when the car is running so i guess its normal. thanks again.
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80 931 intercooled,1 bar, and kinda runs right

5yearplan · Joined: 14 Feb 2013 Posts: 7 Location: Michigan

dredging up an old thread here: if all the fuel pump relay is doing is reading the coil switching, why doesnt it work with MSD ignition? even thou the tach reads the signal fine? is there a resistor i can change out to attenuate the relay to the MSD signal? Or could I wire the MSD tach adapter in with the dizzy impulse sender coax to the relay for a cleaner signal. I tried scoping the signal from the original ECU to pin 1 on the FPR but didnt get any signal

I have a 1982 Porsche 924 n/a with the 433 906 059 relay, and the 6 pin Bosch 0 227 100 010 ECU. The ECU died and I wired in MSD 6 for spark and right now the fuel pump relay is clicking off and on repeatedly during cranking, the car runs on a standard 4 pin relay, but I dont want to disable the crash safety fuel cut off of the relay. thanks

McGyver · Posted: Fri Apr 05, 2013 2:17 am Post subject:

Actually relay needs only (+12V) signal to be trigged - from coil to input 1 in relay. In my relay it don't need to pulse or whatever... works just on +12. So try connect some exit with stable 12V from MSD unit and connect it to 1 on relay... That should work ok.
There are some more ideas

even adding some sensor with trigger wheel to make that impulses for relay - or sensor added to spark distributor if you have one.
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931 82' - 5000km after full engine rebuild

SOLD: 924 81' N/A- with turbo gearbox "dogleg" - great but mysterious car

www.mauser98k.internetdsl.pl - if someone like german rifles (English version avalible)

5yearplan · Joined: 14 Feb 2013 Posts: 7 Location: Michigan

I found i didnt have the green and white connected when looking at the scope... now I see the 12v signal with key on at pin 1 and 15...
I thought the 12v signal was only supposed to be present if the engine was turning over... so now the question is how does the relay shut off in the event that the key is on with the engine not running? I plugged the relay in with the original ecu in the car, terminal 30 is batt(+12) terminal 31 is ground, 15 is 12v with ign on, and so is terminal 1, but 87 doesnt see more than 40 mv? i can also hear two different clicks of the relay, the first is when the key is turned to the first position, the second as the starter starts to engage, but i still have no voltage through the relay

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

During cranking the 15 circuit isn't activated. The coil is energized by the 16 circuit which comes off the 50 cranking circuit at the starter. This is for US cars. Not sure on the ROW's.

Dennis
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81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

5yearplan · Joined: 14 Feb 2013 Posts: 7 Location: Michigan

it is indeed a US car.

I was originally lead to believe that the fuel pump relay would power down if the ECU didnt see engine rpm. More digging has lead me to believe the circuitry in the relay is just a simple 555 timer so that when the key is first turned to ign the fuel pumps prime for a few seconds, then shut off, once the 15 circuit is energized by the starter circuit the relay stays on... so no crash safety? If I understand that the coil(15) circuit is energized by the starter(16) what does the green/white from coil(15) to ECU(15) doing? also as per the diagram the black FP relay(15) goes to ign and (1) green/white goes to the coil(1) and tach via a connector, what is the purpose of this?

When I had first wired in the MSD instead of the Bosch ECU, the relay was cycling as per the timer because I had unplugged the green/white wire(the one that shares the ppl/clear female spade) from the coil(15) to the Bosch ECU which I removed, as well as having the green wire for the tach which also connects with green wire to FP relay(1) connected to the msd grey(tach output) as opposed to 12v ign...

Also I had the MSD orange(coil 15) and black (coil1), the ppl/clear starter wire(16) on the the coil(15) I bypassed the relay with a fused jumper wire from batt+(30) to fuel pump(87) and the car would not start while I was cranking until I released the key from fully turned "start", to "run" position... If I omitted the ppl/clear wire from the coil it would start just fine while cranking, i.e. key at "start" position, again with FP relay bypassed and green/white wire omitted, feeding the grey msd (tach out) to both the tach and FP relay (1)

So do I need to separate the green tach wire from the green/white FP relay(1)?

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

On the standard ignition there are two wires going to the coil. One is the 15 (higher resistance) circuit that powers the coil when the ignition switch is in the on position. The other wire is the 16 circuit (lower resistance for more spark) which runs from the 50 circuit wire on the starter. This circuit only operates when the ignition is in the start/crank position. If you only have the 15 circuit wire hooked to the MSD coil, it won't fire during cranking as you have discovered.

Dennis
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81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black