RF interference in Ford Explorer
Jeffrey L. Bowman, MD
Explorer? I seem to recall a blurb about the source (fuel pump, I
think) a while back. For some reason, there is wideband electrical
RF noise generated that de-senses and interferes with normal VHF and
UHF mobile operations.
If you have any info please drop me a note....
Regards,
Jeffrey
Rhyolite95
pump from the tank and installing filters. If I remember correectly the
fix was marginal and required more filtering outside the tank. Try some
ferrite chokes on the fuel pump leads first and make sure the tank is
grounded well.
Tim Payne
> I must have missed the object of this reply. Would you tell me what
> problems exits with the fuel filters in Explorers? I recently hard
> wired a 2 mtr into mine and, so far, have had no trouble. I hope none
> developes. I noticed that with my HT, I can accelerate while using
> cruise contron when hit the ptt switch. I don't have that problem now
> using the mobile at 50watts.
> Stu
I have a 1993 Explorer with a Kenwood 742A with 2m,220, and 440
installed. I have two seperate antennas. One, a COmet BC-10 2m/440, and
the other a quarter wave 220. I experience the same problem when
transmitting. Sometimes the cruise control will accelerate, sometime
deaccelerate. When the vehicle was wet a couple of weeks ago, even the
rear wiper would cycle on/off!!! Really wierd..I assume that Ford really
never decoupled their computers or feed lines very well. I never
experienced anything like that with my Toyota 4-Runner prior. I have
heard and read a lot of people having the same identical problems though..
73,
-Tim
Clifford Uyeda
>> rhyol...@aol.com (Rhyolite95) wrote:
>>
>> >Yes I remember someone getting the factory fix which involved
removing the
>> >pump from the tank and installing filters. If I remember correectly
the
>> >fix was marginal and required more filtering outside the tank. Try
some
>> >ferrite chokes on the fuel pump leads first and make sure the tank is
>> >grounded well.
>I have a 1993 Explorer with a Kenwood 742A with 2m,220, and 440
>installed. I have two seperate antennas. One, a COmet BC-10 2m/440,
and
>the other a quarter wave 220. I experience the same problem when
>transmitting. Sometimes the cruise control will accelerate, sometime
>deaccelerate. When the vehicle was wet a couple of weeks ago, even the
>rear wiper would cycle on/off!!! Really wierd..I assume that Ford really
>never decoupled their computers or feed lines very well. I never
>experienced anything like that with my Toyota 4-Runner prior. I have
>heard and read a lot of people having the same identical problems
though..
>73,
>-Tim
FORD ARTICLE # 95-11-3 (portions copied here)
A "Whinning/buzzing" noise in the speakers of the entertainment radio or
two way radio on vehicles with an in-tank electric noise from the fuel
pump.
Correction:
Install an electronic noise RFI filter (F1PZ-18B925-A) on the fuel pump
inside the fuel tank. Refer to the following Test Procedure to confirm
that the concern exists, then refer to the Service Procedure for repair
details.
Note: Some light trucks require one (1) RFI filter for each in-tank
electric fuel pump on Mulit-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 the vehicle speed, then it is not the fuel pump and
this fix will not be effective. The following procedure will help
determine if the fuel pump is the cause of the radio noise.
1. Turn on the radio before the key is turned on ( assuming the radio
will operate without the ignition key. You may need to put the ingnition
key in the accessory position).
2. Turn the ignition key to the RUN position (do not start the engine).
3. The fuel pump should run for about 1 second witht he key in the RUN
position with the engine not running. Listen for the 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.
1. Remove the fuel pump sender assembly from the fuel tank. Refer to the
appropriate Service manual, Section 24-35 for cars/light trucks and
Section 10-01 for compact trucks, for removal procedure.
2. ON vehicles without fuel delivery module, remove the negative and
positive connectors from the fuel pump.
a. Cut the wires to the fuel pump 3" from the flange of the fuel pump and
discard the wires.
b. connect the RFI filter connectors to the spade terminal on the fuel
pump.
c. Cut and solder both the red and black wire of the RFI filter to the
red and black wires of the flange. Use shrink tube over the solder
connections.
The above in the entirety, including diagrams, can be obtained from
Patrick Quinn
Ford Motor Company
835 Mason - Suite 200
Dearborn, MI 48124
Article TSB 95-11-3
stu
>Yes I remember someone getting the factory fix which involved removing the
>pump from the tank and installing filters. If I remember correectly the
>fix was marginal and required more filtering outside the tank. Try some
>ferrite chokes on the fuel pump leads first and make sure the tank is
>grounded well.
I must have missed the object of this reply. Would you tell me what
John Meaker
is that a TSB only covers a problem for 1 year. The TSB for the
fuel pump interference in 1993 is 93-15-6. I'm not sure of
any other year than 1995 (95-11-3).
In the computer index it can be found under "Fuel System"
"Noise" and "Radio".
I went to my dealer and asked about TSB 93-15-6, and was told
that it didn't apply to my car, a '95 model. A mechanic working
close by heard the conversation and asked if it was the RFI
problem and I said it was.
He then looked in the 1995 TSB to find the current number. I
asked him if he had done many of these and he replied that he
had done 276 in the previous year alone, and they were easy to
do.
It turns out that the 276 light trucks were for one customer,
the state, who had bought a fleet and wanted radios installed
in them. I don't hear the problem on my 2 meter-440 FM radio.
That might be because the antenna is mounted in the middle of
the roof.
I do suspect that it will show up on HF, though. It was
quite obvious on my previous car, another Ford. Since I
planned to trade in that car, I never did get it fixed.
My dealer seems quite willing to do the repair under
warranty. If not under warranty time charged will run from
2.5 Hours (88-91 Tempo) down to .7 Hours (91-95 Escort &
89-92 Probe). The filter is a really simple RFI filter
with two stubs (PN F1PZ-18B925-A).
I hope this helps.
John Meaker -=- kr4ah
Clifford Uyeda (clif...@ix.netcom.com) wrote:
: >> rhyol...@aol.com (Rhyolite95) wrote:
: >>
: >> >Yes I remember someone getting the factory fix which involved removing the
: >> >pump from the tank and installing filters. If I remember correectly the
: >> >fix was marginal and required more filtering outside the tank. Try some
: >> >ferrite chokes on the fuel pump leads first and make sure the tank is
: >> >grounded well.
: >I have a 1993 Explorer with a Kenwood 742A with 2m,220, and 440
: >installed. I have two seperate antennas. One, a COmet BC-10 2m/440,
: and
: >the other a quarter wave 220. I experience the same problem when
: >transmitting. Sometimes the cruise control will accelerate, sometime
: >deaccelerate. When the vehicle was wet a couple of weeks ago, even the
: >rear wiper would cycle on/off!!! Really wierd..I assume that Ford really
: >never decoupled their computers or feed lines very well. I never
: >experienced anything like that with my Toyota 4-Runner prior. I have
: >heard and read a lot of people having the same identical problems
: though..
: >73,
: >-Tim
So far haven't had any problem with the cruise control or any other
systems in either this car or my previous car (1991 model). I did,
however have the antennas mounted in the middle of the roof with an NMO
mount and the radios were well grounded.
: FORD ARTICLE # 95-11-3 (portions copied here)
Dusty Veideman
>
> Yes I remember someone getting the factory fix which involved removing the
> pump from the tank and installing filters. If I remember correectly the
> fix was marginal and required more filtering outside the tank. Try some
> ferrite chokes on the fuel pump leads first and make sure the tank is
> grounded well.
\
I have a 1994 Ford Explorer and found the same problem when I put in My
HF. I had S9 noise from the fuel pump in the gas tank and partially solver
the problem by putting in a capacitor from the Positive line as close to
the tank as possible direct to the frame. I tried several different ones
until I found an Armaco filter designed for RF interferrance.
This reduced the noise to about an S 2-3. Still not being satisfied,
I wrote to Ford Motors Customers Service in Ontario. Believe it or not
they recalled the vehicle, removed the tank and installed a proper
RFI filter inside the tank next to the pump. No more noise except for
a slight white noise which is not even noticeable. By coincidence,
I found a write up in a motor magazine about the same thing but, I would
suggest contacting Ford directly and complaining about the RFI
on your Ham radio... good luck...
KF0OS
>
> In article <4a9cga$o...@stc06.ctd.ornl.gov>, KF0OS <1...@ornl.gov> writes:
>
> >Does anyone know if this problem/fix is applicable to the Ford
> >Aerostar, as well?
> >
> >KF0OS
>
> I have all Ford vehicles here, and the pumps are noisy in all of them. I
> added external RFI filters at the fuel tanks by using snap on chokes and
> ..1 MFD bypass caps from each lead to the chassis on the supply side of the
> choke.
>
> I also ground the exhaust system, transmission and engine block to the
> frame at several points.
>
> In my F-150/ F-250 vehicles, I ground the cab to the frame at all corners
> and the fenders to the frame at the front. The cab and front end sits on
> several rubber mounts to improve NVH (noise vibration harshness), but it
> causes ground loops in the wiring.
>
> With these changes, I can run 1 kW mobile with no ill effects (except
> headlight dimming). The receiver noise dropped from S9 to S2 or less!
>
> 73 Tom
Guess I have work to do - Thanks Tom.
KF0OS
Does anyone know if this problem/fix is applicable to the Ford
Aerostar, as well?
KF0OS
W8JI Tom
>Does anyone know if this problem/fix is applicable to the Ford
>Aerostar, as well?
>
>KF0OS
>
>
I have all Ford vehicles here, and the pumps are noisy in all of them. I
John Chapman
It's ARTICLE No. 95-11-3 for all 95 Ford trucks and some cars.
The biggest factor (that was missed in previous postings here) is
The very long ground return lead from fuel pump to engine compartment.
This can be as much as 10 or more feet in larger trucks. Great antenna.
Grounding this lead to frame at closest point to fuel tank is absolutly
necessary.
John, N0KIC (From Mark M. Ford Service HotLine.)
Clifton T. Sharp
>I have all Ford vehicles here, and the pumps are noisy in all of them. I
>added external RFI filters at the fuel tanks by using snap on chokes and
>.1 MFD bypass caps from each lead to the chassis on the supply side of the
>choke.
But at what location? Near the gas tank, or near the front of the vehicle?
I would presume the former; if so, how did you weatherproof the whole
thing?
--
Cliff Sharp There are days when no matter which
WA9PDM way you spit, it's upwind.
cli...@indep1.chi.il.us --The First Law of Reality
Rick Trommer
Not to be overlooked is the exhaust system that must also be grounded
to the chassis. Provide at least 3 good ground straps, one before the
converter, after the converter and one at the tail pipe... 73 WB5YTG
Rick rtro...@vnet.ibm.com
Jerry
pumps. If snap on filters work, you are lucky. The pumps are
submergible and require removal from the tank to to install Ford's RFI
kit. Under warrenty there is NO cost, out of warrenty is about $150.
My ruel tank hasn't been the same since, but the noise is gone. Make
sure they seat the tank properly and don't force it back in, else it
will leak and require a new tank...
Jerry N9VHW jerd...@xnet.com
Curtis Wheeler
>
>>In article <4a9i54$o...@newsbf02.news.aol.com> w8j...@aol.com (W8JI Tom) writes:
>>>I have all Ford vehicles here, and the pumps are noisy in all of them. I
>>>added external RFI filters at the fuel tanks by using snap on chokes and
>>>.1 MFD bypass caps from each lead to the chassis on the supply side of the
>>>choke.
>
>>But at what location? Near the gas tank, or near the front of the vehicle?
>>I would presume the former; if so, how did you weatherproof the whole
>>thing?
>
I ran an FT-5200 in my 92 Escort GT without a bit if interference
trouble. I was warned about fuel pump noise too. The pump leads on the
Escort are accessable under the back seat so it would have been easy if
it was necessary. I have a friend with a Kenwood 732 in a '93 F-150 - no
noise or interference problems ever detected. Enough on "other Fords".
I just got a new Explorer three weeks ago. I haven't put the 5200 in yet
- since I haven't figured out where to put the transciever. I would be
interested in hearing from people that have installed two-ways in them.
But what I want to know about is how you installed the radio itself - not
what mods you made to other systems on the truck...
How did you run power? Straight to the battery? Ground to the battery
as well?
What kind of antenna? Mag mount? Roof mount? (Drilled a hole? Where?)
Glass mount? (Where?).
Anyone ever installed other LMR equipment in an Explorer (non-ham gear)?
We have several Spectras running in company Explorers on UHF without any
trouble that I am aware of.
--
Curtis G. Wheeler - Pleasanton, CA
W8JI Tom
>>In article <4a9i54$o...@newsbf02.news.aol.com> w8j...@aol.com (W8JI
Tom)
>writes:
>>>I have all Ford vehicles here, and the pumps are noisy in all of them.
I
>>>added external RFI filters at the fuel tanks by using snap on chokes
and
>>>.1 MFD bypass caps from each lead to the chassis on the supply side of
the
>>>choke.
>
>>But at what location? Near the gas tank, or near the front of the
vehicle?
>>I would presume the former; if so, how did you weatherproof the whole
>>thing?
Missed that question. I have a F150, F250HD, and a Mustang GT. All three
were substantially improved in noise by grounding the engine block, trans,
and exhaust systems at several points. I snapped the bead over the wires
by the tank, and bypassed the supply leads to the chassis at the tank. I
removed a tiny bit of insulation and soldered the cap leads to the wire,
sprayed the new connections with plastic spray, and gooped em with RTV
after the spray dried.
Pulling the fuel tanks is a job, so avoid it if you can.
By the way, be sure the antenna is connected to major sheet metal for a
ground!
Be sure the cab and fenders are grounded, the F series floats on rubber.
73 Tom