HELP: Engine Noise in HF Mobile Installation

Wayne K. Irwin, W1KI wrote:

I have a '98 Ranger that has hellacious ignition noise and other vehicle
noise. I
haven't looked close enough to see if any is comming from the fuel pump. It
even affects the AM side of vehicle stereo system. The dealer says it may
be a bad radio.

Naturally, the dealer says Ford has no bulletins or recalls on this problem.
If anyone knows of any, let the rest of us know.

Tony -- KF3BX

Tony... there is a tech note, recently issued by Ford, that deals with fuel
pump noise in mobile radios. It requires putting a filter on the pump,
which on my Explorer is inside the fuel tank. There were a whole range of
cars, going back five or more years, that were cited in the tech. note.

You can recognize this noise by turning the radio on, then turning the
ignition switch from "off" into the "on" position, but not all the way to
"start." The fuel pump will run for one second, then shut off. In my case,
the noise level jumps to about S7 or 8, which is where it will stay, of
course, when the engine is running and the pump is on all the time. Try it.
If you hear the noise, talk to Ford about the filter.

My explorer is a '74 and they're ordering the filter for me, covered by my
extended warranty.

Good luck... Ed

Tony (and anyone else experiencing the problem),

Are you sure that it is ignition noise you are hearing? Ford products
are infamous for fuel pump noise. You can tell if it is fuel pump noise
by doing the following:

Turn the radio on but do not start the engine. Listen carefully and if
you hear the noise briefly - 1 to 3 seconds, you are hearing the fuel
pump build up pressure in the fuel line. If you do not hear the noise,
then it is more likely to be ignition noise. Don't overlook other
possible sources, gauges, wheel static etc.

Assuming that you do have fuel pump noise, do the following: Go to your
favorite Radio Shack and but a 0.1 uF capacitor. Lower the gas tank and
install the cap across the wires to the fuel pump. I'ts mounted inside
the tank. Ford makes a noise filter that is quite effective but the
cost is somewhere near $70.00, so I'm told. I have a friend in Florida
who did the cap job on his Ford pickup with amazing results. He has 2
fuel tanks and added the cap to the tank he uses most often. He then
made an A - B comparison and couldn't believe the difference.

I am going to make the same mod on my Ford Ranger when I get the time.

Hope this helps.

73,

Wayne, W1KI
ARRL/VEC

Wayne K. Irwin, W1KI wrote:

No offense to anyone but this was too good to pass up.

Wayne tells the guy to go to Radio Shack and by a capacitor

Ed Juge tells the guy to go to Ford

Go figure

Has Ford fixed this problem on the new models? Seems like they have had a
long time to do it.

73
Mark
AB0HJ

: I'm in the process of installing a Yaesu FT-900 in my 1987 Ford
: Thunderbird. I am experiencing noise on the Ford's AM radio and on a
: shortwave portable I used for noise testing, so I expect to encounter
: the same when I have the HF installation completed.

: : Those are the particulars. Can anyone offer advise as to how to remove
: the remaining ignition noise? I have heard that the Ford electronic
: fuel pump also can be the cause of interference; has anyone had
: experience in fixing this problem?

: Thanks for any advise offered.
: 73,
: Tony N8SNC


RFI noise in Ford vehicles

After installing an HF rig in my 97 Ford Explorer, I was disheartened
to discovea S9+ noise level. The source appears to be the electric
fuel pump. I received some excellent info from other Ford owners and
I now wish to pass along some of that advice here.

Ref: Ford Technical Service Bulletin: 98-7-3
"Fuel system - fuel pump: whining/buzzing noise comes thru 2-way
radio speakers"

Vehicles covered:

Ford
1990-93 Tempo
1990-97 Probe, Thunderbird
1990-98 Escort, Taurus
1990-99 Crown Victoria, Mustang
1997-98 Contour

Lincoln-Mercury
1990-92 Mark VII
1990-93 Topaz
1990-96 Continental
1990-97 Cougar
1990-98 Sable, Town Car
1990-99 Grand Marquis
1991-98 Tracer
1997-98 Mystique
1997-98 Mark VIII

Light Truck
1990 Bronco II
1990-96 Bronco
1990-97 Aerostar, F Super Duty, F-250 HD, F-350
1990-98 Econoline
1990-99 F-150, F-250 LD, Ranger
1991-98 Explorer
1993-98 Villager
1997-98 Expedition, Mountaineer, Windstar
1998 Navigator

The Problem:
Electrical noise on radio speakers caused by in-tank electric
fuel pump.

The Fix:
Installaition of an RFI filter (Part No. F1PZ-18B925-A) on the
fuel pump inside the fuel tank. *Note: some light trucks may require
one RFI on each fuel pump on multi-tank vehicles.

Test Procedure:
Fuel pump radio noise is relatively constant and changes only slightly
with vehicle speed. If the frequency of the noise varies, or the noise
comes and goes with vehicle speed, then it is NOT the fuel pump, and
this fix will not be effective. Use the following procedure to determine
if the fuel pumpis the cause of the radio noise.

1. Turn the radio on.
2. Turn the ignition key to the RUN position, but do NOT start the engine.
3. The fuel pump should run for about 1 second with the key in the RUN
position with the engine not running. Listen for noise in the radio.
If the noise is present while the pump is running, and stops when the
pump stops, then the noise is being generated by the pump and this
procedure should help.

Additional comments:
I purchased by own vehicle "used" from a Ford dealer and also purchased
the extended service plan. However, the service manager told me that this
repair would be done under the BASIC WARRANTY and not by the extended
service plan. For what it's worth, the RFI part costs about $70 and
sometimes takes a week or so to be delivered to the dealership. Other
Ford owners have also told me that this fix was done at no charge to
them as well. So if you've got a problem ... perhaps this will help.

Warmest 73,
Sandy W7BX


PS: I did have the filter installed on my '97 Explorer and noticed an
immediate and substantial improvement on 15m; with the use of my noise
blanker, the noise dropped to some substantial noise and I have been advised to properly ground the
antenna to the chassis of the vehicle. For what it's worth, my first
QSO was with JA3CZY on 15m ... so, I guess it works.

Any suggestions for spark noise on Chevy trucks?
NE7X...

And the reply is too good to pass up also. Perhaps Ford is making a few
bucks two ways. They have a "fix" for the problem but it is a bit
pricey for those of us who view ham Radio as a hobby - about $60.00 to
$70.00 for their filter [I've seen one, it looks like it might contain a
capacitor and a couple coils, fancier than the capacitor only idea, but
maybe a little better - it mounts inside the tank.] and I was quoted
about $175.00 to install it. Perhaps, if the vehicle is in warranty,
they will install the retrofit for free, I don't know.

So if you go to a Ford dealer after the warranty runs out, they make a
few extra bucks on the retrofit. The majority of the people buying cars
and light trucks will not know about the fuel pump noise problem since
they don't put radios in their vehicles - so Ford gets to save a little
in manufacturing costs.

Yes, it has been a long time. My Ranger is 8+ years old and I know of
people with newer Ford products who have experienced the same problem.
Don't know about the newest Fords though...

73 to all,

Wayne

Wayne K. Irwin, W1KI wrote:

I have a friend with a 96 Bronco. She does not have an HF rig but the AM
radio picks up the noise when she is in weak signal areas. Would have thought
Ford would have fixed it for that reason.

73
Mark
AB0HJ