[Ict03X]

While towing my 24ft. aluminum enclosed trailer (about 5500 lb. loaded) last weekend my 2003 Excursion started suddenly losing power and fuel mileage (by the gauge) dropped to 4-6 miles to the gallon. I pulled over at the next rest stop that also happened to be close to try and figure out what was going on. When I popped the hood there was an abnormal amount of "whooshing" sound from the air filter (I pulled the element off and the sound continued). Luckily I had a buddy following in his new duramax and he was able to tow the trailer so I could focus on getting home. For the rest of the trip there was a pretty good "miss" and at some rpm/mph there was a pretty good vibration but at 70 mph the miss could be described as mildly noticeable. Yesterday, once home and in the daylight we looked at it again. At idle it is pretty choppy and it misses pretty good while accelerating.

After reading a little on here I thought maybe the EGR could be a possibility but I'm not too familiar with diesels. Also today I replaced the fuel filters in case I got some contaminated fuel. After I changed the filters I made it two blocks and lost all engine power.

Any ideas? Thanks in advance for your help!

Derek

 

[GregH]

Is it smoking?

I would suggest that you've got one or more failed injectors resulting in compression pressure being forced back into the fuel system. It is easy to check - bear with me while I describe the procedure. Of course, stay away from moving parts, hot things, etc. and don't smoke, yada, yada, yada. If you get hurt, it's not my fault.

Take the secondary fuel filter cap off and remove the filter. Turn the key on, and let the fuel bowl fill all the way up. Now turn the key off. Hop out, and look on the passenger side of the engine compartment. Between the right side battery and the A/C case, there will be a single wire connector with a moderate gauge wire in it. Disconnect the connector by squeezing the connector and pulling. Now pull this wire up (you may have to route it around the vacuum pump, other harnesses, whatever) towards the positive battery cable end. Flip up the red cover on the cable end, and touch the terminal in the connector to the stud on the positive battery cable clamp. THE ENGINE WILL TURN OVER WHILE YOU ARE HOLDING THE CONNECTOR ON THE BATTERY CABLE. Steer clear of moving parts, make sure the trans is in park, parking brake on, etc. While cranking the engine, watch for bubbles in the secondary fuel filter housing. Don't put your face right over it - there may be a lot of bubbling! Crank the engine for a minimum of 15 seconds, or until you see bubbles. If you don't have bubbles, then try it two more times.

Post back with results, and we'll go from there.

Good luck, and don't get hurt.

 

[Ict03X]

No smoke...also forgot to mention that the next day the "whooshing" was gone. It's at the dealership now so we'll see what happens.

 

[ciscofreak]

Thanks for the post Greg, some of us appreciate what you guys do here...

 

[GregH]

No problem. I appreciate the note of thanks...

 

[Ict03X]

Not much word from the dealership other than "it's showing some weird codes". I normally play with gas powered fords (01 Lightning and 04 cobra)...do diesels have CEL's? I didn't think there were any codes or I would've tried to pull them with my tuner from my Lighting.

Thanks!

 

[GregH]

The tuner for your lightning wouldn't pull codes from a 6.0L. The 6.0 has got a different communication protocol.

The diesels we have will only turn on the CEL for a select number of codes. it's an EPA thing....

 

[Ict03X]

My wife called me this morning and said the dealership called and said injectors and throttle body were being replaced. Injectors I understand but throttle body..I've never heard of a throttle body being bad (this was second hand from my wife though).

 

[Btravelen]

Throttle body? These were rendered non functional with a flash somewhere along the way. How many and which injectors?

Take care, and keep us posted.