motor diagnosis

[lebel409]

Hi All,

I came home yesterday and the truck started running rough...missing a little at low RPM...So I thought, Dammit, COP...and I stopped at the Autozone. I asked the guy if there was an easy way to tell which COP was bad...He said the OBD should tell me. Well, there were no codes.

So he asks when I last got gas...yesterday morning. So he says it may be water in the gas (after the heavy rain) and so I bought some water remover.

It seemed to run better the rest of the way home, so I thought maybe it was fixed...then got on the freeway:grumble:..running rough again and throws the check engine light. When I got home it showed 1, 3, and 8 missfires, (both side of the motor) so I'm thinking it's not the COP (all 3 going bad at once?).

So now I'm thinking that it was/is water and it's clogging the fuel filter?

2000 5.4 superduty

Any takes would be appreciated!

 

[OCMerrill]

Hi All,

I came home yesterday and the truck started running rough...missing a little at low RPM...So I thought, Dammit, COP...and I stopped at the Autozone. I asked the guy if there was an easy way to tell which COP was bad...He said the OBD should tell me. Well, there were no codes.

So he asks when I last got gas...yesterday morning. So he says it may be water in the gas (after the heavy rain) and so I bought some water remover.

It seemed to run better the rest of the way home, so I thought maybe it was fixed...then got on the freeway:grumble:..running rough again and throws the check engine light. When I got home it showed 1, 3, and 8 missfires, (both side of the motor) so I'm thinking it's not the COP (all 3 going bad at once?).

So now I'm thinking that it was/is water and it's clogging the fuel filter?

2000 5.4 superduty

Any takes would be appreciated!

I have had the fuel filter cause block lean codes on my V-10. A good place to start.

 

[Nuvie]

I run a fleet shop that has several Fords. Boots usually corrects the problem, but if your that far already, plugs can't hurt either.

 

[lebel409]

I changed plugs at 95K...at 142K now

 

[Big Kahunaa]

plugs would be a good idea

 

[lebel409]

Plugs are supposed to be changed at 90K...they were fine, showed erosion, but not fouled...11lbs of torque. So I still have 50K to go...

 

[Nuvie]

The plug boots are notorius for going bad and causing a miss though

 

[lebel409]

I can't conceive of 3 going bad in a day.

Before I filled up I checked the mileage...13.5 per gallon...running great.

 

[charlyox]

I think you got a bad tank of gas.

 

[Zaairman]

$100 question... what type of plugs did you put in? Them Ferds are picky about their plugs...

 

[lebel409]

I was gonna go all Platinum/4 prong/heavy duty...but a kid that works for Autozone told me the same thing...so they are stockers.

I'm gonna try the fuel filter tonight...

 

[Kleptow]

If you have over 10k on the fuel filter start there then plugs, My bets on the fuel filter most people have no idea how must the fuel filter plays into performance on fuel infected vehicles.

 

[Zaairman]

I was gonna go all Platinum/4 prong/heavy duty...but a kid that works for Autozone told me the same thing...so they are stockers.

I'm gonna try the fuel filter tonight...

What do you mean by stockers? What brand?

 

[lebel409]

Whatever the stock replacement was, motorcraft maybe?

So I changed the fuel filter...maybe a bit better but it's still there.

Took my kid to boy scout and he says,"Dad, you truck stinks!". Sure enough, sulphur dioxide smell from the tailpipe...SO that must be the Catalytic converter...Dammit.