Project 4ktq continues to fight me

[Huw Powell]

> I can definitely hear the pump while I am cranking,  Strange thing
> about this car and possibly the root of my problem is that it never
> had done the prime before start, at least not that I can hear. 

As I recall, we decided years ago that the "priming" of the fuel pump is 
  not really a feature but a bug - the relay turns on in reaction to the 
single spike of voltage in the ignition system when the key is turned on.

>  I also moved the vacuum port for
> the fuel pressure regulator from below the throttle plate to above it
> but I can't see how that would make any difference, Vacuum is
> vacuum...

You may be right, but, the vacuum varies from place to place in the 
intake system - of either side of some obstruction, it is certainly 
going to be different.

> I have half a tank of gas in the car and I notice that it seems to
> run longer with the WOT switch taped in the closed position but only
> by a couple seconds.  It's like something is just stopping the fuel
> from going to the injectors...  Be it mechanical or electronic I
> don't know...    It fires, starts to sound like it is running on 3.5
> cylinders and then revs down to 0 kind of a   BRAAAP....BUUUUH  BUUH
> Buh  buh buh ... 

You know, that sounds like a car that is not getting any cold start 
enrichment.  IE, perhaps the temp sender is bad, or the ECU is not 
getting the signal, or the CPA is not getting the extra current to 
increase fuel flow.  You can measure or replace the sender, and measure 
the CPA current during those "half starts" with any luck.  It should 
run, as I recall, in the 30-50 mA range when cold.

> it was running and
> sounded good over the weekend and the only different now is that I
> added two gauges and removed the evaporator from the passsenger foot
> well.  I also removed the vacuum pump that sucks the AC flapper shut
> but that shouldn't affect the engine in any way.....

As long as you plugged the vacuum line to it, no, it shouldn't.  What 
gauges did you add and where did you wire them in?

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/