Fuel pump woes

[Kneale Brownson]

The timing between the crank position and the dizzy should be correct if 
the engine ran before.  That relationship wouldn't have changed.

You can make the fuel pump run--if it's OK and wired properly--by 
jumpering the two large slots in the fuel pump relay spot on the 
fuse/relay panel under the hood.

If you used a new, smaller fuel pump and had to install that different 
wire from the pump to the fixture at the top of the tank, maybe you 
misdirected the wiring?  I think SJM has details on his website.

On 6/20/2013 3:20 PM, Kenneth wrote:
> Speaking of the other sensor, I think another thing to watch for for no-start situations is that if the signal from the hall sensor in the distributor has to coincide with the signal from the timing sensor on the bell housing that looks for the flywheel pin to determine crank position.  The dizzy hall sensor distinquishes between compression and exhaust strokes, etc.  If the two signals don't overlap, then I would imagine it also wouldn't start.
>
> I would imagine tho', that those crank/distributor position sensors have more to do with whether a spark is sent than if the fuel pump runs.  I would expect the fuel pump to run if the rpm sensor alone was sending a signal.
>
> Does the fuel pump cycle when you turn the key to "on?"  On my car you can hear it run for a moment when you turn the key on, before cranking.  If the pump doesn't do that then I would look at something other than the timing sensors.
>
> Kenneth
>
> ---- Kneale Brownson<kneale at coslink.net>  wrote:
>> Don't forget there are two sensors, the engine speed and the timing, and the ECU needs a good signal from both to allow a start.  If they're OEMs, they're old!!  They're not as exposed to heat as on a V8,  but they still can fail.
>>
>> Sent from my iPhone
>>
>> On Jun 20, 2013, at 2:01 PM, Kenneth<auditude at cox.net>  wrote:
>>
>>> FWIW, I've heard of heat-related (and possibly possibly intermittent) failure of the timing sensor.
>>>
>>> Jay Kempf<jkempf at madriver.com>  wrote:
>>>> The relay is powered only when the computer let's the car run. The computer has to know the car is either trying to start or running to allow the fuel to flow. The computer can only know if the engine is running if it sees a signal from the crank position sensor. So if either the computer is dead on that channel, the crank position sensor is dead or intermittent or the wiring from the crank position sensor to the computer or to the relay is out you won't get any power to the relay
>>> .>>Robert Bade
>>>>> Short version of where I
>>>> am. Replaced the steel fuel lines, didn't know the age of the fuel pump
>>>> so replaced it [it was original], replaced the fuel filter. I did
>>>> nothing electrical other than the new connector to the fuel pump. My
>>>> problem, I get no power to the fuel pump. I jumpered power to slot 52 of
>>>> the fuel pump relay mount [#10] and get no power back at the fuel pump
>>>> harness. It gets odd now, I checked continuity of the wires from fuel
>>>> relay mount to the fuel pump harness and both power and ground are fine.
>>>> It makes no sense! Am I missing something obvious? Fuses are good,
>>>> battery is good. The Audi gods have been testing me lately, seriously
>>>> pushing me.
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