My car has been giving me the SES light. I went to autozone to check it out and they said it as a 1641 - Fuel Pump Primary Circuit Failure.

Now, my car has been running. Yesterday I noticed a slight bog at lower RPMs.

I looked under my hood and noticed this connector was loose click here for picture. (fuel pump prime connector) Someone else on the board told me that shouldnt be connected.

So I though maybe the pump relay. First of all, Im not sure which two wires I need to put on the multimeter, coming out of the relay adapter, to check for voltage.

Second, my repair manual says "Turn the ignition to on (do not start), and you should hear the fuel pump activate for aprox 2 seconds". Well when I turn the ignition on it doesnt activate, but when I turn the ignition off, it does activate. Is this normal?

I hear the pump running when the car is on. Any suggestions?? How do I go about testing the relay to make sure it works?

 

Bobby, have the fuel pressure checked, that will tell you right there...if the pump conitnues to prime itself, it is probably bad

 

Am I supposed to hear the pump when I turn the ignition to on, or for 2 seconds after I turn it off?? Or both?

 

The fuel pump should run for about 2 secs. when you turn the key on, not off. The best thing to do to check out the fuel system is to check the fuel pressure. You can buy a gauge at advanced auto parts for about $35 that connects right into the fuel rail.

 

That code has nothing to do with fuel. Autozone seems to be famous for giving out erroneous info.

P1641 Fan Control (FC) relay 1 control circuit

Maybe you have a manual fan switch? It can cause that code.

 

And for a lack of better words, the fuel pump sounds like a high-pitched whirl sound? Kind of like.. hmm a small, fast electric fan?

 

Did you get that off the Autotap webpage? I got the same thing, but thought it might of meant Fuel Control.. But yes, I have a manual fan switch.. I wonder if one of my resistors in the line went out.

Wonder why Autozone said Fuel system

 

That is from the factory service manual. There is a page of all the trouble codes on my Tech Page.

Clear the code and then make sure your fans work when you turn on the a/c (pretty much the easiest way to check them). If your code comes back when you first run your fans with the manual switch, then it is probably the culprit.

 

I should've checked your webpage to begin with!

Thanks for the help.. Im thinking one of the resistors either came loose or blew. I was at the drag strip showing someone the wiring, and I think one of the connections came loose.

I guess that means I now have to find why Im getting werid power surges and bogs sometimes.

 

could the fact that his fuel pump is coming on when he turns the key off possibly mean that he has a bad igintion switch. Maybe the insides are bad or corroded? Just a thought. Weird power surges and bogges occasionally and a pump that comes on when you shut the car off seems to me to be ignition switch related.

 

Does anyone have a sound clip of the fuel pump so I know I am hearing the right thing?

 

Here is a sound clip of me turning on my ignition, waiting a few seconds, and turning it off. The "whirling" sound Im talking about is after I turn the ignition off. But now that I listen closer, I hear a slight whirl when I turn the ignition on. If you can hear it also, is that my fuel pump? If so, what is the whirl sound when I turn my ignition off?? (sorry, Im still new to LT1s)

Click here for Sound MP3

 

Man, sounds like a dentist drill, I would get your fuel pressure checked asap....