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P0420: Catalyst System Efficiency Below Threshold (Bank 1).
Your vehicle's Computer Monitors the efficiency of your catalytic convert through the use of 2 oxygen sensors. There is on before the cat, which is supposed to send a fluctuating signal to the car's computer. The one behind the cat is supposed to have a steady signal that changes very little. This code is set when both sensors begin to send similar reading to the computer and it can mean that the cat is no longer disposing of harmful exhaust gases or one of the sensors is no longer functioning.
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What are the rear speakers for a 1998 Ford Expedition?
all the door speakers are 6x8 on the 98 ford expedition.
Show you how to replace ignition coils for a ford Expedition 2003?
98 expedition
What causes battery light to come on On a 98 Ford Expedition?
what causes the battery light to on a 2005 ford expedition to come on?
How many lugs are on 98 Ford Expedition?
On a 1998 Ford Expedition : There are ( 5 lugs for each wheel , total of 20 )
Does a 98 ford expedition have 3 row seats?
Yes
Where is the ecm located on a 98 Ford Expedition?
Where is the ECM located on ford expidition 4.6
Where is speed sensor 3 on a 1998 Ford Expedition?
where is speed sensor location 98 ford expedition 4.6 engine nocruise control
How much is it for a oil pump for a ford expedition 98 v8?
$70.00 !
How do you reset the alarm on 1998 Ford Expedition Eddie Bauer?
i have a 98 ford expedition xlt the remote does not work how do i reset the alarm so it will work
Where is fuel pump in 98 expedition?
On a 1998 Ford Expedition : The ELECTRIC fuel pump is INSIDE the fuel tank
What is the fuse box diagram for a 98 ford expedition?
purchase a chiltons manual
Where is the fourth cilynder in a 98 Ford Expedition 4.6lt?
firewall 4 - 8 3 - 7 2 - 6 1 - 5 front of Ford Expedition
