Secondary fuel pump dead?
 

Car runs fine, except when at full throttle going through the gears. Then acts like fuel shutoff. For short bursts of full throttle, everything is ok. I'm thinking the secondary pump isn't keeping up, or only the primary is working.

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Re: Secondary fuel pump dead?
 

Most likely yes. To confirm perform the fuel pumps amperage test on the red pigtail at the wiper motor. Your meter will read 7-9 amps if both are running. 3-4 amps if one is running. Details in the Stickies.

Re: Secondary fuel pump dead?
 

Do you still have the Secondary Port Throttle (SPT) system still in place?
If so, test the vacuum pump and each of the vacuum actuators. A failure of any 1 of those 3 items can cause the same symptom.

Re: Secondary fuel pump dead?
 

Secondary Port Throttle (SPT) system is still in place. Entire system was checked by Marc when my 415 was built less than a year ago. Vacuum pump doesn't cycle at all. Pretty sure its a pump. Will be replacing both today.

Re: Secondary fuel pump dead?
 

My first check was the current draw. Current reads 9.3 Amps, so it seems both pumps are running.
Next check will be fuel pressure.

Re: Secondary fuel pump dead?
 

Fuel pressure check.... not good.
Only 42psi at cold idle.

Re: Secondary fuel pump dead?
 

I really am disappointed in aftermarket Chinese parts.
After replacing both pumps with Delphi FE0039 units, I now have a combined fuel pressure of 20psi.....

Re: Secondary fuel pump dead?
 

If the vacuum pump doesn't cycle at all, how do you know if it is still working?

Re: Secondary fuel pump dead?
 

Vacuum pump does cycle, just not excessively. About once every 45 seconds after initial pump up.

Put old (original) fuel pumps back in for now.
After removing and replacing the assembly 3 times, I'm now an "expert".

Re: Secondary fuel pump dead?
 

Any recommendations for "good" fuel pumps?