If he drops the "in" end of the pump into some fuel with a known good
hose to connect it, and it still produces bubbles, then he knows that
they are coming from the pump  and not anything upstream, like the
tank. If someone else can do the same test with another pump and
provide the results, he will know if his pump is causing the problem.

I believe that the pump is not the problem. I have never know bubbles
to cause a surge in RPM. When that happened to me I had to adjust the
switch on the AFM.

Jim

On Thu, Jul 15, 2010 at 6:41 PM, John Rodgers <inua@charter.net> wrote:
> �Sounds like pump cavitation to me! Dunno how you would check it though.
>
> John Rodgers
> Clayartist and Moldmaker
> 88'GL VW Bus Driver
> Chelsea, AL
> Http://www.moldhaus.com
>
>
> On 7/15/2010 4:19 PM, Sam Payne wrote:
>>
>> The injectors were cleaned recently, and have only seen about 3,000 miles
>> since. Also, the fuel
>> pressure with the pump running tests dead on, and the residual pressure
>> stays up for long
>> enough.
>> � � I haven't tried disconnecting the O2 sensor, and will. Thanks for the
>> suggestion.
>> � � �But why the bubbles?
>>
>> � � � � thanks, Sam
>>
>>
>