[s-cars] Mysterious fuel pump problem at start

[Jerry Scott]

My guess is that it is the check valve in the fuel pump that is not 
holding the line pressure. The nose up attitude aggravates the problem 
and allows the fuel to drain back to the tank very quickly.  You then 
have to crank until the line fills with the check valve open.  I had 
this problem and fixed it with a can of BG 44K ($22 at NAPA)) in 16 
gallons of gas.  This seemed to clean the valve so that it would hold 
pressure again.  Or, just change the fuel pump (in the tank), which 
contains the check valve.
Jerry

hartmann wrote:

>Here's a little intermittent problem I've been struggling with for a while.
>
>About eight months ago, my '95 S6 was driven from Santa Cruz to San 
>Francisco and parked on a hill (facing up hill) for about 10 min.  Came 
>out, S6 wouldn't start.  Moved the car to a flat spot and it started.  
>This near exact thing happened three more times.
>
>Then it happened on the flat area at a gas station.  After cranking the 
>car for few minutes, I talked to the mechanic at the station and came to 
>show him what was going on and ... yes, viola, the S6 starts without a 
>problem.  Clearly, the car is developing a sense of humor.
>
>With some help from Lou @ Dieter's in Mountain View, we tried a few 
>things and with replacing the fuel pump relay, the problem vanished.  
>Hooray!
>
>Until last week.  It's back -- random fuel pump outage at startup.  I 
>think it's the relay again, but why would that happen twice?  I'm 
>wondering if there's another issue.  You have any ideas?
>
>BTW, if the car starts, it runs fine.  It has so far, never (knock on 
>wood) had a problem after it starts.
>
>Thanks,
>
>Hartmann
>'95 S6
>_______________________________________________
>S-CAR-List mailing list
>S-CAR-List at audifans.com
>http://www.audifans.com/mailman/listinfo/s-car-list
>
>
>
>  
>