So I'm towing about 10,000 pounds with an '04 350 4x4 in stock mode. When I'm going 70, I'm turning about 2000 rpms. When the motor begins to lug a bit, it 'coughs' and lurches(like it lost power for a split second) and a puff of smoke comes out the tailpipe. Is this normal?

 

I forgot to add:
Sometimes, it sounds like an electric fan kicking on but if I play with the throttle, the rpms of it (whatever is spinning) goes up and down with the rpms of the motor.

 

Do you have a Check Engine Light when this happens?

 

Moved to 6oh...enjoy

 

No check engine light, no overheat, no tranny heat up. The Ford dealer said today the the EGR valve is bad. Thoughts?

 

40searay,

EGR valve sticking is the most likely problem.

 

I had a similar symptom a few months ago.

Dealer cleaned EGR and since the ECU had flagged a "low boost" code, replaced the turbo. All for the $100 deductible. They also gave it the latest flash (changed from buzz to induction heating of injectors flash).

So far, so good. TY Ford Warranty.

 

40searay,

I had what sounds like the same issue a couple of weeks ago. At first is sounded like a clutch fan, then loss of power puffs of black smoke. Dealer said most likely EGR. Called back and said it was the turbo. One C-note later refurb Turbo. Truck pulls like new.
Good luck!

 

Same problem here. Dealer replaced EGR and Turbo. Sound gone for now.

 

I sure hope it's not the turbo. I don't want to find out halfway across Alligator Alley!

 

Searay40,

When my truck had this issue I was returning from Montana. I was towing an empty three horse trailer. The "coughing" started as I was West bound on Hwy 80 just outside of Boomtown. I barely made it to Donner Summit rest stop. After sitting for about 20 minutes I thought what the heck and drove home. Set the cruise at 60. Not a single problem the rest of the way home. Nezt day I tookm it to the dealer. 37,000 miles. This is the only issue I've had.
Very thankful it didn't go bad in hte middle of no where.
Cheers,
Wilbur

 

I got it back from the dealer today. The service order says:
"performed pinpoint test codes P0401, P404 Run EGR tests and replace EGR valve. Retest & verify repair. All OK."

When I got it home, I read the codes and got a P0603 code. The ford site says:
"P0603 Internal Control Module KAM Error"

Does anyone know what a KAM error is?

 

Caused when the battery was disconnected when the tech worked on the vehicle. This is normal and you will get it anytime you reset the KAM memory or reflash the PCM.

 

Thank you sir!

 

Well, I pulled the boat home and it ran much better. No coughing! However, the pulling power of this truck is underwhelming at best. I'm not sure if it's the motor or the load but 10,000 pounds should be handled better by a truck capable of pulling 13,000. On dead flat land, the best I could do was about 75 and I could only get that by easing the throttle down and keeping it in overdrive. If I put too much throttle on, it would downshift and if I mashed it to the floor, I could get about 74-75mph but the rpms would be about 3,000. When I got to my towing speed (70 MPH), it would be in 5th? gear at about 2500 rpm. If I eased off the throttle, I'd get overdrive, rpms at 2000 and could maintain 70 mph but no more. When I got to the Sunshine Skyway bridge, I got my best running start, mashed the throttle and could only get 50 mph over the top. I can't imagine running this truck with a load in a hilly state!!