Fuel pumps are silent, even when I short out #7 and #8 per fuel pump relay. The question now is how do I confirm it is the pump. I just don't believe two pump could die at the same time. Is there a fuse besides the fuel pump relay that is in the fuel pump circuit?

A couple days ago, I got about 6.5 amp between #7 and #8, I got nothing today. Does that 6.5 amp indicating only one pump is working? The car has been pretty slow in accelation from standing lately.

Should I short out #7 and #8 and then measure the voltage between two posts on the fuel pump?

Please help.

Well, just to make you happy(ier) I just found a nest of mice had eaten through all 4 wires to the pump on a 1984 Alfa Spider !
They had made themselves at home under the reinforcing plate over the gas tank.....$291.44 OEM pump because it just so happened, the pump decided to take a dump at the same time...

Was working fine last week.

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[http://languageandgrammar.com/2008/01/14/youve-got-problems-not-issues/ ]

"A liberal is someone who feels they owe a great debt to their fellow man, which debt he proposes to pay off with your money."

go to the fuel pumps and "rap" them with a piece of wood or handle of screwdriver to see if they are sticking, if nothing, I would check for simple power coming to the fuel pumps when the key is in the on position, I don't know if your model has a fuel pump relay, my 95 sl320 did not start and after a couple raps the pumps came to life and the dealer replaced both, let us know outcome

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Jerry

2004 SL500 Black 55K Miles
2002 s500 Black 90K Miles
1986 300E Gold 233K Miles
1966 Twin Cessna 320D
1989 Jeep Cherokee 233K Miles
1994 Ford Van E150 399K Miles

Is there any thing other than battery, fuel pump relay, and pump? How do I check if there is any power going into the relay seat?

As of right now I got not current across #7 and #8. Which one is teh ground so I could check the voltage coming from Battery?

the only thing i would do differently is have someone crank the engine while you hit the pumpwith a piece of wood, make sure it is in park and e brake on

Just read the CD and got 13.5 V between 11 and 8. So the power is coming to the relay seat. However, I have not figured out a way to measure voltage at the pumps yet.

There are two posts on each pump and there is rubber cap over the post. How do you remove that cap? Could I just measure the voltage between those two post, while the #7 and #8 of the relay is short?

If I got voltage and no action, then I will just need to buy two pumps.

pull the caps, they were soft rubber, now probably hard rubber, the bolts from the pupms are different sizes, the large is negative, and the small is positive, make sure you put a 10 amp fuse in your jumper. if it is not fused it could burn some wires.

Many thanks to all who helped.

I built a connector set with an 8A fuse and short out 7 and 8. Taking off the plastic cover over teh pump, I knocked on them pretty hard. Hissss, one of the pumps came back on. Now I will be able to drive the car up a ramp to work on it.

One nice gentleman is sending me a pair of FP N/C. I will work on it this coming weekend. It should not take me more than 4 hours to get the pumps in, provided I have a way to get a full tank of gas out.

How do I do that (get a full tank of gas out)? The fuel line is too hard to clam. I don't want to drive it again until new pumps are on.