Bucking F150

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Dec 30, 2004 | 02:19 PM

#16

alan2244

New User

Joined: Nov 2004

Posts: 23

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don't drive vehicle if it exhibits signs of bad COP or plug?

Quote:

Originally Posted by grafekie

OK, called the dealer, he "phone diagnosed" it as a plug or COP problem, and told me not to drive it if its showing signs, which it is. A tow truck is on its way (my friend won't use the car-hauler she has access to because she broke it and isn't allowed to haul cars with it anymore...) and hopefully I will have it fixed before tonight. :-/

Don't drive it? I don't think you can hurt the engine by driving it on 7 cylinders. Is there something else going on here that I'm not aware of and driving a truck with a bad COP will damage something?

Thanks all!

Jan 1, 2005 | 02:37 AM

#17

fbodyfan

Senior User

Joined: Sep 2004

Posts: 385

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From: Missouri

You probably can hurt the engine by driving on 7 cylinders. The firing isn't balanced the harmonics and vibrations could end up breaking rods or even the crank. Pretty much, if your truck is bucking like he says it was, don't drive it. Something's obviously out of sync, and engines don't like to be out of sync. Bad things happen.

Jan 2, 2005 | 04:38 PM

#18

grafekie

Thread Starter

Fleet Mechanic

Joined: Oct 2004

Posts: 1,496

Likes: 3

From: Simpsonville, KY

Ditto. That's a crudload of force flying around in that engine, I wouldn't want things getting banged up or bent. $80 tow, or new engine.... I'd rather spit out the $80 and not worry about it.

Jan 3, 2005 | 12:08 PM

#19

PaulC

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Joined: Sep 2002

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Quote:

Originally Posted by northsea

Just reading threads. What is the cop? What is the coil?

Northsea
Just bought the 99 F150 4.6L auto 138L miles.

Your 1999 F-150 should have a different ignition system, known as EDIS. This system uses two coils, one each mounted at the front of the cylinder banks. Each coil has four good old fashioned all-American spark plug wires running from it.

Lower tech than the 5.4 or 2000+ 4.6 engine, but a bit easier on the wallet, and much less prone to antifreeze-leak induced failures.

Jan 3, 2005 | 01:04 PM

#20

kman2785

Junior User

Joined: May 2002

Posts: 91

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hey,

I have the same problem with my 1997 f150 4x4.

This weekend i went to the desert and was hitting the mud puddles. My truck did awesome until it was time to leave! I noticed a "bucking" well i pulled over and found the bottom of my air filter was wet and so i dried it and drove home at a speed that my truck wouldnt buck at.

The next day i changed my air filter, cleaned maf, and reset the computer. The engine ran great and seemed fine.

On my way to work the truck started to buck again so i went home and read this forum!

This forum has been a lot of help, but i have the two seperate coils with the "good old fashioned wires" any ways do you guys think my problem is one of the two coils?

Also i too noticed my mpg drop and a performance loss the week before i went to the desert.

Thanks Kelly

Jan 4, 2005 | 02:37 PM

#21

PaulC

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Joined: Sep 2002

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Before I recently changed my spark plug wires at 75,000 miles, I would notice some bucking if it was raining out, or if I had recently powerwashed the engine compartment. Since the new wires, no bucking. Old wires begin to develop small cracks in their insulation which could allow water to make contact with the wire core. Might be your problem. A bad coil might also be the problem. Hard to tell from where I'm sitting.

Jan 4, 2005 | 06:01 PM

#22

kman2785

Junior User

Joined: May 2002

Posts: 91

Likes: 0

well

I bought a coil and that didnt fix the problem, checked a lot of connections to see if they were wet, checked fuses, pulled a few spark plugs, blew the spark plug tubes dry; if wet, checked fuel injectors, ... i cant seem to think of anything else but plug wires or the pcm?

the truck is ticking me of if you know what i mean.

I am thinking about taking it to ford for a diagnostics check because the engine light was on but like i said i unhooked the battery and the light hasnt come back on.

Any ideas?

Thanks kelly

Jan 5, 2005 | 08:15 AM

#23

BillyBob69

Lead Driver

Joined: Jul 2003

Posts: 7,404

Likes: 52

From: Wheatland, Mo

Depending on how long you had the battery disconnected, it probably still has the codes in memory. You can go to a local parts store and have them pull the codes for you instead of the dealer who will charge you an arm and a leg. Most parts stores will do it for free.