[s-cars] Help. Difficult Start--Fuel Pump Relay or something else

[calvinlc at earthlink.net]

Don't forget about the fuel pressure regulator.  It's a lot easier and
cheaper to try first than the fuel pump.  You can confirm it's fuel,
although I am 99.9% convinced it is just by your description, by simply
shorting out the fuel pump relay for 5-10 seconds before trying to crank the
engine.  If it decreases your crank time prior to engine start then you have
your culprit as fuel.  The FPR is in the back of the fuel rail, is $35, and
takes 15 minutes to change.
--Calvin


-----Original Message-----
From: s-car-list-bounces at audifans.com
[mailto:s-car-list-bounces at audifans.com]On Behalf Of Mark Strangways
Sent: Thursday, November 17, 2005 4:52 PM
To: janagnos at earthlink.net; s-car-list at audifans.com
Subject: Re: [s-cars] Help. Difficult Start--Fuel Pump Relay or
something else


Sounds like the check valve at the fuel pump (or near).
I had similar issues for warm starts.

The ECU does not seem to prime the system until it sees the engine actually
run.
I found that "flooring the gas" would get the fuel pump started earlier.

Eventually I blew some compressed air (low pressure) down the supply line
and it cleared whatever jammed it.

Mark S
----- Original Message -----
From: <janagnos at earthlink.net>
To: <s-car-list at audifans.com>
Sent: Thursday, November 17, 2005 8:09 AM
Subject: [s-cars] Help. Difficult Start--Fuel Pump Relay or something else


Oh great wizards of the Audi community I need some insight/direction.

My 94 S4 is starting to show its age (170K).  In the past week it has
developed a difficult to start issue.  It requires a good 6-10 sec of
cranking before it would fire.  Once it started it would run great. I went
through the fun of installing a new pump last night (that was a joy) and
the issue has improved but only a little as it requires maybe 3-5 sec of
cranking.  Even if I turn the car off then try to start again it is better,
but not the old turn key and 0.5 sec later ignition.

What I do not seem to hear is the priming of the system when the key is
turned to the on position? Do our cars do that becuase I can't remember?  I
know my wife's '01 A6 does, as does my '05 GM truck.  Heck I remember my
old GTI having a short (2-3 sec) run of the fuel pump prior to start.  I do
hear some clicking off of a relay when the key goes to the run position,
but that's it.

I will end with I do not have any pressure guages to hook up to determine
the pressure loss in the system.  And I have been operating on the basis
that the issue is purely fuel related.  I have not looked at the ignition
at all.

Any insight would be greatly appreciated.

Thanks

Jason

'94 S4
Stock and still having fun at 170K

--------------------------------------------------------------------
mail2web - Check your email from the web at
http://mail2web.com/ .


_______________________________________________
S-CAR-List mailing list
S-CAR-List at audifans.com
http://www.audifans.com/mailman/listinfo/s-car-list

_______________________________________________
S-CAR-List mailing list
S-CAR-List at audifans.com
http://www.audifans.com/mailman/listinfo/s-car-list