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MrWizard's avatar
MrWizard
Moderator
Oct 16, 2018

1997 Ford 460 ignition

since last week, ive been experiencing engine 'run while driving' problems

it starts great, then will NOT accelerate properly, or hesitates, bogs etc..

it started right after i filled the gas at my regular stop

after (2) days of this i added a can of sea foam

and things started improving over the course of several days

this morning it was 'slow' again, i went to gas up and filled up with premium , NOW its back firing and acting even worse

the questions i have are multiple

1997 bounder F53 chassis, 460 CuIn
where are the fuel filters, i can't find them

where are the ICM and EEC MODULES located i can't find them either
all the chassis manual says i have them

i'm thinking filters first and electronic modules 'next'
might be a good idea to get them and have them on hand
even IF not needed at this time

Onan generator is running fine, so i really don't think its a continuing fuel issue, although there could be contamination in the bottom of the tank, below the genny pickup, which has clogged the drive engine fuel filters
i was leaning heavy toward fuel issue until the backfiring started

part numbers and locations needed
and advice
thank you

28 Replies

  • Fuel filter is on the left frame rail, about mid ship. You can buy the clip release tools at any parts store. The set is cheap. I have no corrosion problems with the clips on my 95 F53. The problem starting after fueling would indicate fuel filter. If the filter don't correct the problem, you need to run a fuel pressure test while driving. About 32 lbs of pressure at idle and about 38 lbs at wide open throttle. Fuel pressures are important. The ECM is dependent on designed pressures for proper air fuel ratios. Your fuel pump is of turbine design and does not get noisy when failing. Just running the test while sitting still will not prove or disprove the fuel pump.
    I suggest OEM motorcraft replacement fuel pump, if needed. That way you change the sending unit too.
    Rockauto/Motocraft fuel pump.
    Thin film ignition (TFI) is on the left, outside firewall, under master cylinder, on heat sink. If you elect to replace the TFI, make sure to get the gray one. The black TFI won't work on you MH. Your EEC-IV is in front of the steering column, next to floor. There is a 4 digit "catch code" on the ECM. You will need that code if you elect to look for a replacement. For example, 95 catch code looks like this "MOOØ".

    Richard
  • The fuel filer should be mounted somewhere along the side rail. You need a special tool to replace it. WARNING ! At that age, the connectors MAY be corroded beyond use. If so, new connectors will need to be spliced in. Use a Motorcraft replacement filter (likely a Motorcraft FG872 - less than $10).

    The fuel pump is IN THE TANK. Before replacing do 2 simple tests. First, crawl under the back so that your heard is near the fuel tank. Have some one switch the ignition from OFF to ON (not START). Bad fuel pumps are very noisy.

    Rent a fuel pressure tester and check the fuel pressure. Specific number are not as important as the pressure staying consistent at idle and at high idle (about 2000 RPM).

    If you do decide it is the fuel pump, the job is not too bad as long as the tanks is EMPTY. Yes, you have to drop the tank ! I recommend Bosch, Denso or Delphi (Delco) fuel pumps. Sometimes you can buy just the fuel pump, but most times it is the complete assembly: pump, pickup, sock and fuel level sender. For the extra $50-$100, probably worth it.
  • Pump...
    Ok before I crawl nose to tail 36ft under this thing
    Where is this pump located ?
    Rear near the gas tank, or hiding up front

    Ken ...Delco what.... Filter or pump?
  • Ford's 460 , chronic fuel pump issues.when you change it out ,be sure to use ac Delco or motorcraft fuel ....Ken
  • Change the fuel filter then check your fuel pressure. Sounds like a typical failing fuel pump. Low pressure will also cause backfiring.
  • My gas tank holds 75 gallons so once a year I add five cans of Seafoam before a long trip. Each can treats about 15 gallons of gas. I run my Onan generator at least an hour while the Seafoam is in there.

    When was the last time you replaced plugs and wires?

    At night can you see any cross firing between spark plug wires?
  • My 1996 Dolphin 460 did the same thing. It ended up being the fuel pump. The rail pressure was low. The problem being intermittent made it more difficult to find. The fuel filter is on the drivers frame rail inside in front of the tires. You need a Ford fuel line doohickey to change it out and watch for the gasoline squirt it seemed to have a check valve. It has been a while.............