cranks over hard after sitting loss power and mpgbut

[eds20065.9l]

my 2006 5.9L cranks over hard after it sits a few hours or over night it rolls over right amount of times just acts like bats are low but they test good when it starts it puffs a little white/blue smoke but goes right away smells like fuel not coolant. the truck does not miss or run rough but has loss power and mpgs . reman injectors 11,000 miles ago but feed tubes where not changed local shop said it was not needed . i took it back when this problem started they did fuel press before cp3 and after and return test they checked out good then said the feed tubes needed retourqed charged me 300 bucks and said it was fixed . i got it home and the next morning it was the same thing so i am looking for answers any help is appreciated thanks

 

[lpennock]

Sounds like an injector going out.

 

[eds20065.9l]

I was told the injectors cannot leak into cylinders over night because there is no pressure in the system once the truck is off how else would fuel leak into the cylinder

 

[cerberusiam]

I was told the injectors cannot leak into cylinders over night because there is no pressure in the system once the truck is off how else would fuel leak into the cylinder

You were told wrong. There is pressure in the system on shutdown and it is common for a bad injector to dribble into the cylinder after sitting for a while.

Please define "cranks over hard" better. Are you saying the engine spins slow when the starter is engaged? Are you saying it slow to start after sitting? There is a big differnce between a slow crank and a slow start so better definition will help diagnose.

 

[lpennock]

I was told the injectors cannot leak into cylinders over night because there is no pressure in the system once the truck is off how else would fuel leak into the cylinder

Most hard starts are injectors, you may want to read this link. Tech Feature: Diagnosing Diesel Injector Problems

 

[eds20065.9l]

It cranks over hard starts to rollover good then hits a hard spot just like it starts to hydrolock local shop told me it was impossible for injectors to do this because there would be fuel in the oil I just don't understand why it couldn't be the injector copper washers or a o ring but I am not a diesel tech just a tinkerer great with the old Chevy's but first diesel

 

[eds20065.9l]

I have not been driving my truck for fear of causing further damage i was told that if it locked hard enough that it could bend a rod i would really like to get it figured out. a few places have told me that it was the injectors and others have told me that it was the copper washers letting return fuel leak down into the cylinder any other ideas?

 

[cerberusiam]

If it was hydrolocking you would see massive clouds of white smoke not just little puffs. The little puffs after sitting indicates an injector that is not seating the pintle correctly. Probably less than a teaspoon of fuel is actually drbbling out over the course of time and it will just sit in the injector bowl until the engine fires. That is where an initial puff on start comes from.

The starter hanging as it starts to crank is something else, like a bad starter or flywheel\flex plate gear, a bad battery, a bad battery connection, etc. Check the cabkles and connections closely, especially the cross over cable, and have the batteries load tested individually.

 

[eds20065.9l]

allready had the batts and connections tested and they did a amp draw test on the starter, the engine starts fine if it is restarted within a couple hours with no smoke just first thing in the morning or after 8-10 hours at work. my local shop give up on it and i dont have as much cash as i did when it went in so now i am stuck trying to figure it out my self thank you for the suggestions but they have already been covered by the shop, well i hope anyway. mabey i will recheck them tommrow

 

[cerberusiam]

An amp draw test on a warm starter is not going to find a hang when it is cold unless it is in the armature. If it is a mechanical drive problem it may only show cold. Some problems like that intemrittent hang in the starter require disassembly to see or just replacement to cure. If it only does it cold it could still be a battery issue or more likely starter.

The copper washers seat the injector in the bore and unless they are loose it is not going to leak. Clearances are tight enough carbon will stick the injector in the bore, diesel is not going to easily bypass it. The o-ring is above the injector port from the cross over tube and will keep the fuel in the head return gallery out of the oil and has nothing to do with white smoke on start up. You would be making oil if the o-ring was bad.

I GUARANTEE if there w2as enough fuel in the cylinder to hydro lock it even a little you would know something is wrong. You would likely run from the truck when it fired because it would knock so loud you would expect pistons and rods to fly out anytime, if they didn't. Of course, you would not be able to see any of this becasue the truck, your driveway, and half the neighborhood would covered with a HUGE cloud of white somoke from all the uncombusted slightly warm fuel pushed out the exhaust. Like, blot out the sun cloud of white. The FD would be called. LMAO!

The smoke is an injector hanging, almost positive. I have seen it half dozen times and it always the same thing, bad injector. What you might have is just gummed up injectors if you have not been using additives. It is worth a shot to do an injector cleaning. Get yourself a can of SeaFoam, a quart of TWC3 2 stroke oil, a quart of Power Service, and a quart of Marvel Mystery Oil. Add the PS, 2 stroke oil, and MMO to the tank then fill it with good clean fuel. Drain the filter housing and fill it with the SeaFoam. Start the engine with the SeaFoam in the filter and let idle for 30-60 seconds. shut it off and let it sit for 24 hours.

Now go drive the tank out and see what happens. Unless you have a rod bearing starting to hang causing that hitch in the cold start driving it should not hurt it. If it does it is something that was close to happening anyway and ther eis no way short of a tear down to find that. My guess is a new starter and a thorough fuel system cleaning may fix your issue.

Good luck and post back any other questions or info you get.

 

[eds20065.9l]

hey cercerusium thank you for taking the time to enlighten me on this issue. I appreciate the advice and will give your suggestions a try. By the way i have about 2 months left on injector warrenty i was wondering if i should take them and have them tested before the warrenty is up?

 

[eds20065.9l]

hey cercerusium thank you for taking the time to enlighten me on this issue. I appreciate the advice and will give your suggestions a try. By the way i have about 2 months left on injector warrenty i was wondering if i should take them and have them tested before the warrenty is up? Would the injector hang up cause lack of power and poor mpgs

 

[cerberusiam]

Definitely if there is a suspect one like now. How may miles on them and where did you get them from? Who installed them?

 

[eds20065.9l]

They are bosh remans at $355 ea I have 11,000 mi on them. the shop is edlin auto in Ionia Mi. they were the only place everyone recommended and the one that give up recently. The injectors came from diesel injection service in Pottersvill Mi. They have one year warranty and were installed last sept. sorry about murdering your name before

 

[cerberusiam]

If they were true Bosch remans they should replace them no questions asked. Since you are having to deal with another party that complicates things a bit but if they are willing to stand behind their stuff all that is left is identifying the which ones are the problem. A cylinder contribution test might point oyu in the right direction but not always when they dribble. We have had to replace a couple Bosch remans right out of the box because they just did not perform well and the test showed they were off. I have even had to replace new one because it was off balance just enough it created a fuel knock and a wobble in the engine at a certain rpm.

Remans are sometimes a crap shoot but if they are Bosch they should stand behind them as they know not all of them come out perfect.

 

[eds20065.9l]

So since I an now tackling the job do I just take them out and have them all tested at the injector shop or is the contribution test need to be done in the vehicle first not sure how that works and is that a balance test? Local shop mentioned a balance test but not sure if they did it.

 

[cerberusiam]

The contribution test has to be done in the vehicle and is sometimes called a balance test. A balance test can also be run in the rigth machines to more accurately gauge how the injector is delivering the fuel.

I would have a cylinder contribution test done to see if anything jumps out and sayas "here, replace me".

 

[eds20065.9l]

Not something I can do my self is it ,probably need some special equipment? For the test that is, already bought feed tube puller for injector removal

 

[cerberusiam]

You could with the software. StarScan, DRBIII, AutoEnginuity, etc. It is an elkectronic test that measures the duty cycle of the injector solenoid to give a relative read on how they perform. Its not perfect but can help pin point problems sometimes.

 

[eds20065.9l]

ok i was just wondering if i could skip that test and just have them checked at the inject shop or would their test not be enough i was also going to replace the feed tubes since local shop dident or is that not important at this point. thank you for putting up with such an amiture i can rebuild a old 350 chevy all day long but when it comes to this i am as lost as you can get . but by looking into it removal and install is pretty simple, and i dont want to give cash to a shop that has already gave up on me once and dealer hear is about a crooked as they get.