Truck shaking violently, check engine light on, just after oil change, please read more detail below........

Okay ladies and gents, my 1999 F-150 is Sick and I need some help (diagnosis). I took my truck in last Friday to have the oil changed (Every 3K miles for me). I currently have 80,000 +/- miles on it. About 5 minutes after leaving the service center, my truck started shaking very badly at highway speeds (60 MPH) and at a complete stop it shook so badly that I thought it would fall apart.

After about 1 minutes of this violent shaking, the check engine light came on. My immediate reaction was "they must have forgotten to put oil in my F-150!!!" Well, they didn't forget, as I pulled over and checked it immediately. I took it right back to the service center and they hooked up the code reader, which stated that I had a mis-fire on cylinder-x. (Can't remember exactly which they said.) Anyway, they said it was probably a spark plug that had fouled out, but they did not change F-150 5.4L plugs due to the labor intensity.

So I took it to another service center (who I trust) and they made sure that there were no vacuum lines loose or connection issues on the plugs. No problem was found there. So today they changed all the plugs and my truck is still having the same mis-firing problem, causing it to shake violently.

So friends, please tell me, what could it be? I am already out of $$$ due to the change in plugs and the labor involved. Tomorrow they said they would start with the coils, etc. Anyone else have this problem and if so what was the solution? I am by far no mechanic and would greatly appreciate any help. Please help!!

-Silver99

PS Sorry for the long post, but wanted to be as descriptive as possible.

 

I had a similar problem at one time.. it ended up being the coil pack.. have that checked, especially if it is the #4 cylinder.. they tend to have problems with anitfreeze dripping onto them and making them go bad.. dm

 

silver99,

Get your bill out and look at what they serviced. Did they Check the Air Filter? PCV valve? etc... Go over every componant to make sure it was put back in place properly. Did they top up any fluids? Check tranny oil level hot at idle and look for low or over fill.

Regards

Jean Marc Chartier

 

Well, the problem is fixed! Turns out that I needed a coil pack on the #7 cylinder. Thanks all for you responses!

 

I was going to say your problem was either fuel or spark. Just for next time, that includes plugs, coil packs on the 5.4L, or injector. I had a coil go bad too, although it was not shaking so violently running on just 7 cyls.

 

Yep that is usually what happens when a coil pack goes out that is the first thing that should have been checked though after the misfire code came up. You had all those plugs replaced for no reason I think if I were you I would be asking for some of that labor charge refunded that was misdiagnosis on there part and you should not have to eat the cost of that. Wish I would have found this post a tad bit earlier.

Richard D.

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Just had my second one die today. The first was at 36000 miles. Then I just had the head replace (blown spark plug), now the coil went out. I have gotten to where I can diagnose it with out having to hook it up to the computer. I have spent $3000 on the truck in the last 30 days. Time to sell it.

Erin

 

I had that problem with the freeze plug dripping antifreeze on the coil and causing it to go bad too. New coil and freeze plug and problem solved.

 

Should of bought a Dodge

 

Andrew V

Should of bought a Dodge

Just curious but if he should have bought a Slodge and you own a Slodge then why are you on an F150 site? Maybe you wish you had a Ford huh?

Richard D.

WHILE YOUR HERE CHECK OUT MY GALLERY:
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