Archived fuel MPG problem

[Kedzierski]

well i had high fuel consumption problems so it was time for new injectors. I got a new set of BD 90hp nozzles and i sent my injectors to have them rebuild and flow matched. They went back in the truck and power and milage was around over 22mpg for about 3000 mile. Truck started to smoke more and more and now milage is down to around 9 mpg. It also takes around 5 to 10 seconds to start. I drive the some road to work empty every day. I have replaced filter(3 micron) on my fass pump at the some time when injectors were replaced and now around 6000 mile since then i replace it agin and there is no change in fuel consumption or power. I cut open the filters and i found nothing in it . They looked like new. I have no fuel in oil and this week i noticed some thing very strange. As i was fueling up the truck i noticed steam coming out of the filer neck as it would be on fire. I stoped imideatly and it scared me a little because my first though was that my truck is on fire. I looked under the truck and there was no fire so i started pumping fuel but more steam come out. Not sure what to do now. My fuel pressure is at 20PSI and rail pressure seems to be at 24k as well. Any ideas?????

 

[Sticks]

Do the 3rd gens have a regeneration cycle for the cat? Sensor in the exhaust system?

 

[Kedzierski]

no there is no sensors on the exhaust.

 

[Kedzierski]

bump... ... ... ... ... ...

 

[Missouri Mule]

Kedzierski, are you located in cold country? Seems the steam (vapors) would be caused by putting warm fuel with cold fuel or vise versa (possibility you have water in fuel?).

Also the pressure relief/rollover valve could be stuck in closed postion(located on top of fuel tank module).





Hard starting could be caused by bad injectors,fuel control actuator, lift pump going south,air in fuel system.



Rail pressurse seems to be running a little high, getting close to popping the pressure relief valve.



Put two cans of ashless outboard motor oil in fuel tank and see if that helps the start situation if it does you need a new fca if doesn't check out injectors.

 

[Kedzierski]

I am in Ottawa Canada but I had diesel trucks for many years and never seen steam before. It was around -14C when it happened so it was not to cold. I am also seeing a lot of carbon come out of the tail pipe. I started the truck indoors for like 30 seconds and noticed black dust all over the ground.

 

[Missouri Mule]

Do you have boost and egt gauge? What are they reading?

If your getting black smoke your getting to much fuel or not enough air.



You need to find out if the computer is throwing any codes(cel light mite not have lit up).



Rail pressure should be Ok you should have another 1000 to go.

 

[Kedzierski]

yes i do. Boost go up to 35psi no problem and EGT are the some as usual. At 55mph i am at around 800 with i think is a little higher then usual. i got this codes.

P0336 Crankshaft Position Sensor Performance

P0483 Cooling Fan Speed

p0336 come on because of my TST r49 power box.

 

[Missouri Mule]

Have you tried unhooking the power box(s) and going back to stock?

800 seems to be 100 to 150 degrees to high for 55.

Common Rail's have an electronic fan correct? Can you tell if your temp gauge is running hotter or cooler than before?



I would say some one is borrowing your diesel form your tank except for the fact your blowing smoke and your egts are little higher than normal.

 

[Sticks]

...

800 seems to be 100 to 150 degrees to high for 55...



I would say some one is borrowing your diesel form your tank except for the fact your blowing smoke and your egts are little higher than normal.

The engine/ECM may be compensating for cold intake air temperature/trying to build engine coolant temps by increasing fuel and timing.

 

[Kedzierski]

The engine/ECM may be compensating for cold intake air temperature/trying to build engine coolant temps by increasing fuel and timing.

as you mention this i do remember hearing my fan starting at times when my temperature gauge was just under half. I also remember hearing it come on and off at other times. How do i check this possible problem?

 

[Kedzierski]

Have you tried unhooking the power box(s) and going back to stock?

800 seems to be 100 to 150 degrees to high for 55.

Common Rail's have an electronic fan correct? Can you tell if your temp gauge is running hotter or cooler than before?



I would say some one is borrowing your diesel form your tank except for the fact your blowing smoke and your egts are little higher than normal.

i did go back to stock and there was no difference in fuel consumption. City or hwy its no deference in consumption. It seams to run a little higher then usually and lots of black smoke.

 

[Sticks]

I am not a common rail guy, so I am just speculating on possibilities based on general automotive engine controls.

Common rail, Catalytic converter, and other emissions related crap installed causes a variety of problems when something goes skitzo. The more computer controls (sensors) you have, the more likely you are to have "Health" issues over something simple, like a cranky sensor or weak ground.

 

[Missouri Mule]

Someone with a Factory Service manual would have to confirm that the ECM/PCM(if 2003 still have one) is controlling the fan and speed of it. I would imagine the the Coolant temp sensor is sending data to a computer which tells the fan to run or not to run. But the fan might have it's own sensor.

A very state of the art scanner/computer mite be able see what the sensor readings are to the fan.



On my 82 Buick the coolant temp sensor wires got rubbed bare and they touched each other the computer told the carb(electronic) to dump more fuel into the cylinders causing the engine to stall out because it thought the engine/coolant was over heating. I had it towed home (by my Mom driving my van), taped the wires with electrical tape and all was well.



Third generations have had problems with wires going to the fan damaged. near the radiator I believe.

 

[Kedzierski]

Well today i have a new problem. I got in to the truck this mooring. It was around -8C and the truck took around one minute to start. It started idled very ruff and when got wormed up it was ok. After around 60 miles of driving i stoped at my house and it idled and it died. I tried to start it and no go. I cracked one of the injector lines and there was no fuel at all. I loosen it a little more and cranked it fee times and still no fuel. I took my FCA out and it did not rattle so i am assuming this is my problem. There is no codes... Would FCA give high MPG or no start when it starts to go?

 

[Missouri Mule]

I don't know if would give you high mileage but it will definitely cause a no start! The FCA can act up with out the ECM showing a code.

Can you can confirm you are getting fuel to the cp3.

 

[S.Morris]

+1 on fuel supply to inj pump.

Steve

 

[Kedzierski]

I don't know if would give you high mileage but it will definitely cause a no start! The FCA can act up with out the ECM showing a code.

Can you can confirm you are getting fuel to the cp3.

i have fuel all the way up to cp3(21psi).

 

[Kedzierski]

i did more test today and got it running with a little quick start. What i found out is that my rail pressure is at 5500 psi when ideling and at 10500 psi to 11000 psi at cruising speed(55mph) around 1400 to 1500 rpm. At full throttle the most i got was 16500psi. Tomorrow i will tray to swap COV with my brothers truck and see if i can get my rail pressure back. No codes.

 

[KMyrick]

Just my 2 cents.



The wires that go to my fan got cut and tore chunks out of my fins. No loss in MPG at all. Hope that helps a little.