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  #1  
Old 11-19-2006, 11:48 PM
wbain5280's Avatar
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Maybe I Found My Problem (One Of Them)

Today, I was checking the 420SEL project car. I started it up, it starts fine now due to the diode I added to the fuel pump relay, and it was running really poorly. So I checked the fuel pumps. One is easy to check and the other is back behind it. While I was checing the hidden pump, one of the wires came right off complete with alot of corrosion. Looks like I have some rewiring to do.

I'm not getting an O2 signal either. I'm going to clamp on a ground wire and then check the signal, using my O'scope.

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Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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  #2  
Old 11-23-2006, 02:11 PM
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One inop fuel pump on a dual pump set-up can cause problems. I don't recall if it is just starting problems or running problems or both off hand. Maybe after getting good connections at the pumps you can try running without the diode you added?
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  #3  
Old 11-25-2006, 11:10 AM
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Yesterday, I replaced the broken wire on the fuel pump. Both pumps run but running is no better. When I jumped the fuel pump relay sockets 7 and 8 to test my fix, I heard fuel circulating in the hoses and pipes in the engine compartment. Maybe my fuel pressure regulator is bad.
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Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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  #4  
Old 11-25-2006, 04:05 PM
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If your problem is at idle, you can momentarily pinch off the return hose. You could also run a fuel volume test, then see how the fuel looks also after the volume test. Never heard of someone making a comment on hearing fuel circulating.
Gilly
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  #5  
Old 11-25-2006, 08:38 PM
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The diode I added only works during starting to power the cold start valve. It serves no other function.

Why does it sould like there is air in the lines? Fuel pressure regulator, accumulator?
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Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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  #6  
Old 11-25-2006, 08:39 PM
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Quote:
Originally Posted by Gilly View Post
If your problem is at idle, you can momentarily pinch off the return hose. You could also run a fuel volume test, then see how the fuel looks also after the volume test. Never heard of someone making a comment on hearing fuel circulating.
Gilly
There is no sound in my 300SE. Maybe I need a fuel pressure tester.
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Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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  #7  
Old 11-25-2006, 08:42 PM
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Not sure on the noise.
What are the problems (symptoms) with the car?
Is that a single wire or 4 wire O2 sensor?
Gilly
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  #8  
Old 11-26-2006, 10:16 AM
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The O2 sensor is a 3 wire. I can't get a signal on it after replacing it with a generic three wire, soldering the connections and using heat shrinkable tubing. I plan to add a test ground wire on the case.

Could the air sounds in the fuel lines be caused by a bad accumulator by the fuel pumps? By a bad fuel presure regulator?

My bad running otherwise might be caused by bad cap, rotor and wires.
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Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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  #9  
Old 11-30-2006, 11:23 PM
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During the day, I clamped off the low pressure side of the accumulator. The car seemed to run better, but not great. Now I need to measure the amount of fuel delivered. I'm off to the dealer to get an accumulator and a trans vacuum modulator, which seems to be bad given the amount of white smoke coming from the tailpipe.
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Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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  #10  
Old 12-03-2006, 08:05 AM
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Oxygen sensor

How do you check the oxygen sensor on your 420sel?
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  #11  
Old 12-03-2006, 11:52 PM
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Quote:
Originally Posted by aermotor View Post
How do you check the oxygen sensor on your 420sel?
The connections are under the false floor on the passenger side. Take out the carpet, unscrew the plastic bolt and remove the false floor. The connections are on the left hand side. Unplug the green wire and hook up the VOM/DVM/O'scope of your choice.

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Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.
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