06 issues with long crank times.

[MAshley]

I have an 06 3500 6speed that is basically stock like it came from the factory. Only modifications are an air compressor “Kilby” and a Pac brake exhaust brake. Other then changing the oil, air filters fuel filters, and a new set of batteries a month ago “ Diehard Platnum” the truck has been a great work horse, It has pulled many a equipment trailer with loads ranging from empty to almost 26K GCVW so it has been worked well. I would say 75% of its life it has been towing. Its not a grocery getter by any means.



I have an issue now with cranking, it cranks a really really long time. To the point where it doesn’t fire and I stop because it just seems too long.

It almost acts like I changed the fuel filter and or its losing its prime. On a long sit it takes a long time but short waits it firs reasonably quick.

I don’t drive the truck much anymore, maybe 500 miles this year.

I have not noticed increase in oil level.

In fact it uses a little between oil changes.

No fuel smell, like a broke line would give.

Just past 100K miles. Like 100,200 miles LOL

I do notice that if I just drive for a while and then I floor it especially with a load behind it say from a stop light I can actually get some black smoke to come out the tail pipe, not a plume but I can defiantly see the change in color. it usualy last until Im up to speed and then it done the next light shows little, its like it has to build up. I assume it from the use of the exhaust brake. It has been doing this for about the past 10K miles… I assume this is just accumulation over time, but never the less a change.



Again noting has been modified or replaced. its was a work truck... . now its my RV pulling truck



Looking for ideas

Thanks

Dave

 

[Prairie Dog]

Your 06 will smoke a little if you get on it hard - thats not unusual. I have a buddy with 12k on his 06 and has always smoked just a bit with heavy load going uphill under full throttle.
I hate to say this but the most common cause of long crank times is bad injectors.

 

[cerberusiam]

Yep, injectors is the most common problem and the most expensive.



There are other components in the fuel system but they are about as hard to track down as the injectors. FCA, rail relief valve, lift pump can all contribute, as can a worn CP-3.



Do you run addtives? A couple tanks with a mixture of Power Service and 2-stroke oil would be worth a shot to see if possibly the FCA is sticking.



A full diagnostic will include injector return flow test, cylinder contribution test, and rail pressure comparisons between demanded and supplied under different scenarios.



Gauges and start tracking what is going on during driving is priceless. How is the fuel mileage? Any changes?



The CAT on these trucks is more of partuculate trap than anything else. Its normal to see black smoke when getting on it hard after periods of steady cruising. If you can create smoke constantly time after time with no low rpm operation between blasts its a issue to investigate.



Are you seeing and grey smoke under normal throttle operation or cruising?

 

[HTMorris]

My 06 at 99000 miles had long crank times sometimes, black smoke on the highway in 6th. The injectors were leaking down is why it cranked so long. Replaced all 6 injectors. Good to go now.

 

[skr06quad]

I had a long crank time issue with my 06 when it had about 24,000 miles on it. It was still under warranty and the dealer diagnosed a faulty fuel pressure limiting valve in the injector pump as well as a faulty engine control module. Both were replaced free of charge and the truck has started quickly since then, and now has over 86,000 miles.

The mechanic who worked on the truck explained that the pressure limiting valve would relax or fail to seat properly, and allow the high pressure fuel in the fuel rail and pump to leak off and drain back into the fuel tank. The system would then have to re-prime itself before sufficient fuel pressure was present to start the truck. I'm still a bit fuzzy on the reasoning for replacing the ecm, but since it was done on Chrysler's dime I didn't argue. My fuel economy jumped up slightly after the repairs, which was an unexpected bonus.

A good shop should be able to install a test gauge on the high pressure lines and check for a low fuel pressure condition when the hard start happens. You might need to leave it for a few days in order for them to duplicate the symptoms.

Good Luck!

 

[JJPage]

Injectors are not receiving the the pressure they need... . you can replace the Cascade Valve on the CP3 injection pump... .

Before you do that, and free of charge(if your handy), retorque your injector cross tubes to 37 ft lbs. You will need a 24mm and a 19mm crows foot, to fit your torque wrench.

This is an easy procedure, and often overlooked, try it 1st.

 

[MKing7]

When did your long crank times start? After the new batteries or before? I only ask because I was having long crank times and was worried I had a bad injector but I put a meter on the batteries while my wife cranked the truck and the voltage was dropping really low. I replaced the batteries and it fixed my issue. So, just wondering if it could be battery swap related (got a bad battery or damaged/loose connection). Free to check so worth a shot.