I have an 03 Excursion with a 6.0. It is a 4X4 with 152K miles on it. Sometimes while driving it sputters. Almost like it was a gas motor missing. It will drop 2-300 RPMs and then picks up and runs fine. The only thing that has ever been a problem on this truck is that I had to have a few injectors replaced and a new fuel pump put on at the dealer. That was 2 years ago and the truck ran great till the new problem. It started back in December and I took it in to the dealer thinking it was injectors again. They said there wasn't anything wrong accept that it needed an update to the Fuel Injection Control Module. After that it ran fine until about a week ago. I have changed the oil, both fuel filters and have run many tanks of fuel through it. It doesn't throw any service engine lights. And only does this for a second or so and then runs fine. There is obviously something wrong with it but I don't want to take it back to the dealer if they aren't going to find anything.

Also I have an air raid filter on it and when it misses it sounds like air is coming back up through the air filter.

Any ideas?

Thanks

 

Air coming back threw the air box is called a Turbo Fart

It sounds Like you might be having some turbo issues

It could be a sensor that controls turbo operation or might just need to Clean the turbo

Due to the after market Air filter setup you might have Dusted the turbo sounds like it needs to come out for a Cleaning

OEM air filter setup is the Best if you still have the OEM air filter setup I would throw it Back ON

Do you Have any gauges???

Need to monitor MAP,BARO (and maybe EBP but being an 03 EBP maynot be figured into the Calibration IDK worth a Try IMO) at KOEO need to be within 0.5 psi of each other

 

Would a bad sensor not trip a code or show up on the dealers scanner? I have a Boost and EGT gauge. I will try to look and see if it is loosing boost when it happens.

Any way to test the sensor? I took the turbo out and cleaned it a few years ago. It doesn't do this all the time and it ran perfect for two months after the dealer updated the FICM. Is there a way to test anything or is splitting the turbo the only option?

Can you give me some more details on the KOEO test? I will see if my scanner can check that stuff.

 

Sounds like the problem I had a few years back:

It was a coked up turbo that turned out to be the problem for me. Getting your turbo cleaned might do the trick, you may have a unison ring sticking or something like that.

 

If it had a code at the time it was in the dealer yes they would have seen it
Sometimes the PCM wont Light the CEL imediatly it may take a few drive cycles with a bad sensor/reading for the PCM to Light the CEL

just depends if its something thats continuously monitored


With air blowing back threw the Air Box (turbo Fart) you have an Over Boost condition NOT under boost

You can test any sensor
All sensors use a Volt reading to transfer the Sensor Value from the sensor to PCM

If the Value is out then it sets a CEL
Also you can have a DTC (Diagnostic Trouble Code)without a CEL

KOEO = Key On Engine Off

I use a ScanGauge II to look at the MAP,BARO,(and EBP on some models) these are some of the sensors used in determining Boost output because there Pressure Sensors

A scan gauge makes reading these sensors easy
But I suppose you could use a DVM if you knew what Voltage = what PSI

 

BTW it would be best to fix it soon because OverBoost could lift the Heads off the Deck
And Might want to look into a SGII it would show you alot of diffrent sensors Values

160.00 for SGII either from an autozone or here www.scangauge.com