Started running rough while driving..
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Joined: Mar 2021
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If the Cat is melted (restricted exhaust), it was caused by the missing cylinder.
A very expensive misfire.
A misfire passes raw gas that burned in the hot cat. That how it gets melted.
And very likely the rear Ox Sensor has it's tip melted.
If one of the codes was a 420 or a 430, that is how the Cat was detected as possibly blocking the exhaust.
Fuel injection does not stop when a misfire (spark is missing) is from a faulty coil.
Fix the missing cylinder first, then evaluate the exhaust for blockage.
Good luck.
Last edited by Bluegrass; Jun 5, 2022 at 11:31 AM.
98 F150 5.4L E40D/4R100
Joined: Nov 2006
Posts: 28,519
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From: MI
NM Bluegrass basically posted what I did...didn't see the post.
Although, it may be a good idea to pull the connector for injector #5 if you need to drive it that far to the mechanic.
Although, it may be a good idea to pull the connector for injector #5 if you need to drive it that far to the mechanic.
Last edited by Jbrew; Jun 5, 2022 at 11:43 AM.
Thread Starter
Member
Joined: Dec 2013
Posts: 66
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From: Williamsport Pa/S Jersey
Does it make sense to change #5 plug and see it it fires...Possible the wire is bad etc...Hate thinking I might have to drive an hour and IF something goes wrong I'll have no phone service(mountains)...