No Start Unless Block Heater Is Used???

[HBarlow]

A friend called me last night and asked me if I had ever heard of a truck that will not start without use of the block heater even in mild temps as warm as 50*. I have never heard of such a situation and can't imagine why. Have any members experienced or heard of this condition?

The truck is a well-maintained 2005 Ram with 200k miles on the clock. It has a fresh fuel filter and the lift/transfer pump have been checked and determined to be working normally. The truck runs good and idles smoothly once started.

The problem is it simply will not start at all even when the ambient temp is 50*. If the block heater is plugged in for maybe 30 minutes it will then start and run fine. It has been this way for a while.

Two friends who are former Dodge dealer mechanics are baffled by this and I don't have a clue. I suggested replacing the FCA just to eliminate it because it is cheap. This may be done next week. I also suggested having a dealer run the engine diagnostic routine but both the guys who are asking this question were formerly employed by the local Dodge dealer and said there is nobody working in the service department there who could run that test properly and provide good information.

My guess is a new set of reman Cummins injectors is going to be the cure but my '06 was running strong on original injectors at 230k when I sold it.

Anyone know what to do? Your thoughts and suggestions will be appreciated.

 

[jelag]

Hi Harvey...

This is a guess based on the Fords we used to own. .

I had one of my Fords do this a few years back before we switched to the Dodges... . we found that the fuel system was bleeding down and picking up air... when the key was in the crank position the fuel pump doesn't run... .

Try this... turn on the key for 15 seconds, turn off the key, turn on the key for another 15 seconds and than crank the engine... . 2 things should happen...

The fuel pump should charge the system fully, and the grid heaters should do their job...
On the Fords it was glow plugs... but if now the truck starts, there is an air leak allowing air into the fuel system at the engine... . and or the grid system is non-functional. . test and repair. .

In your case, the block heater warms the system so what little bit of fuel is present will fire and start the engine... .

How we found it, was to give it a little bit of starting fluid... they'd fire right up and run... or leave them plugged in... of course with the grid heater you can't use starting fluid... .

Hope this helps. .

 

[CDonaldson]

A friend of mine had the same problems, it was the injector washers/seals - or at least thats what he called them. His problem started out the same way. Then some time later, because he kept just plugging it in to get it running, after he plugged it in and got it running then he'd get somewhere and it would not start again. He opened the water drain, ran out some fuel, and it would start again.





CD

 

[Bill Stockard]

Check the fuel rail pressure while it is cranking both before the block heater is plugged in and after.



Bill

 

[HBarlow]

Thanks for the replies. Please keep the ideas coming. I'll let the suggestion list grow until tomorrow then pass them on to my friends.

 

[JJPage]

A friend of mine had the same problems, it was the injector washers/seals - or at least thats what he called them. His problem started out the same way. Then some time later, because he kept just plugging it in to get it running, after he plugged it in and got it running then he'd get somewhere and it would not start again. He opened the water drain, ran out some fuel, and it would start again.





CD

I'm with this idea..... I would retorque the injector cross tubes to 37' lbs. It's free, if your friend is handy. Remove the intake horn, disconnect the injector lines and check the torque on the cross tube lock nuts, if they are loose or unevenly torqued, you have found the culprit.

 

[CDonaldson]

BTW - he opened the water drain on the fuel system. The truck is a 2004.



CD

 

[HBarlow]

Thanks to each of you who offered suggestions. I will call my friends this morning and pass your ideas on. I am confident your ideas will lead them to correcting the problem. I'll insist that one of them let me know the final outcome so I can report it back to you.

As always, the TDR membership knows the answer!

 

[AH64ID]

The few times I have heard of this its generally from faulty injectors.

 

[RobertHiltz]

Jelags suggestion on running the lift pump without cranking is a good thing to try. Not sure if you need to bump the starter anymore when you key on to run the lift pump but you might have to.

 

[LSchulz]

Does it act like it develops an air leak and loses fuel prime when it gets cold? I would think the CR engines would start pretty easily with a bump from the starter to run the lift pump, and then a short bit of cranking. I had a similar issue on my truck, but only at about -10º. Even then I was able to get it started (and it was unplugged the whole time).

When you say it won't start at all, does it act like it wants to start? Or does it just crank away without a hint of firing?

All this aside, if it's below 50º and the truck won't start, but then he plugs it in, and it starts right up, that rules out any air leaks in the fuel system. It's not like running the block heater will suddenly reprime the things. So, the problem has to lie somewhere else. I'm going to bet that there's a bad sensor someplace, or batteries that are just a touch weak. The CR engines won't open the injectors until the engine is turning at a certain speed, and maybe having the truck plugged in helps it crank that little bit faster, or helps a failing sensor give a better reading when it's warmed up.

 

[Wingate]

Harvey... Any codes? Have him do the cycle key 3 times thing and verify there are no codes appearing.

Does he get any fuel smoke out of the tailpipe when cranking during this "no start" condition? This would indicate that fuel IS being injected, but cylinder is too cold to burn completely. IF there is fuel smoke present(usually whiteish when its only partially burnt at low cyl. temps. ) Check the intake grid heater... It may be damaged. Diesels REALLY don't like to start on cold fuel in low ambient air conditions.

Of course, there could be a fuel system issue ie. . injectors, pump... May need to check rail pressure during cranking. .

Also, do some searching, wasn't there some old threads about hard start/no start conditions that required software updates???

 

[HBarlow]

Does it act like it develops an air leak and loses fuel prime when it gets cold? I would think the CR engines would start pretty easily with a bump from the starter to run the lift pump, and then a short bit of cranking. I had a similar issue on my truck, but only at about -10º. Even then I was able to get it started (and it was unplugged the whole time).

When you say it won't start at all, does it act like it wants to start? Or does it just crank away without a hint of firing?

All this aside, if it's below 50º and the truck won't start, but then he plugs it in, and it starts right up, that rules out any air leaks in the fuel system. It's not like running the block heater will suddenly reprime the things. So, the problem has to lie somewhere else. I'm going to bet that there's a bad sensor someplace, or batteries that are just a touch weak. The CR engines won't open the injectors until the engine is turning at a certain speed, and maybe having the truck plugged in helps it crank that little bit faster, or helps a failing sensor give a better reading when it's warmed up.

My understanding from the friend who called me to ask the question was that the engine would simply turn over but never fire at 50* ambient temp. He said that once the block heater had been activated for about 1/2 hour, it would fire up quickly.

Both the guys who were asking were former Dodge dealer techs with a lot of experience working on Cummins powered Rams so I assume a level of knowledge and competence.

I never thought of a marginal sensor. I will pass that suggestion on to them also.

 

[HBarlow]

Harvey... Any codes? Have him do the cycle key 3 times thing and verify there are no codes appearing.
Does he get any fuel smoke out of the tailpipe when cranking during this "no start" condition? This would indicate that fuel IS being injected, but cylinder is too cold to burn completely. IF there is fuel smoke present(usually whiteish when its only partially burnt at low cyl. temps. ) Check the intake grid heater... It may be damaged. Diesels REALLY don't like to start on cold fuel in low ambient air conditions.
Of course, there could be a fuel system issue ie. . injectors, pump... May need to check rail pressure during cranking. .
Also, do some searching, wasn't there some old threads about hard start/no start conditions that required software updates???

The guys who asked me to ask for advice on TDR are former Cummins techs in a Dodge dealer. They said no codes and normal startup, normal idle, and normal running after started.

This was an '05. I don't remember any old threads about software updates on an '05 and my '06 never had or needed any.

 

[HBarlow]

I called one of the friends today and read him all the suggestions that had been posted here at that time. He said they were going to send the truck owner down to a dealer in another town to have rail pressure read. He said if rail pressure was okay they would inspect the injector tubes and seals as suggested.

I asked him to be sure to let me know what they eventually discover so I can pass it back to those of you who contributed ideas.

Neither of my friends who asked for help from TDR own Cummins powered Rams so they are not TDR members but both of them know full well about the great source of information the TDR membership is.

 

[subodh]

i had the same problem on my 05 and sure it was injectors at that millage their starting to get abit bad quite often.

but it can be cranking speed. .

cause cr engines we have dont open injectors before it has a minimum pressure while cranking. and while cranking a cold engine is alot harder than a hot one it will incrase cranking speed with abit hotter engine.

so maby check railpressure

but my guess is that returnside of his injectors is bad. . some valves letting abit of your pressure go to waste.

the same time my problem showed up i noticed that abit warmer it starts fine. . or startbunny will give it some. .

another thing is to try put a bottle of 2stroke oil in and se if you

can start it then. .

im not a mechanic but theese ideas is from musch reading

and crying over injector prices

 

[JJPage]

He said they were going to send the truck owner down to a dealer in another town to have rail pressure read. He said if rail pressure was okay they would inspect the injector tubes and seals as suggested.

If the injector cross tubes have fallen out of torque spec, that will directly affect rail pressure because they leak. I believe the ecm has to see 3500psi before it will allow the injectors to fire. The tolerance between the cross tube and injector body is so close that the difference between a cold and warm block could create this behavior.



If the cross tubes are leaking,the leaked fuel travels through a passage in the head to the return fuel line at the back of the head, it is not a visible leak. A high quantity return flow test on the injectors will identify a leak somewhere in the system, either a cross tube, cracked injector body, or leaking injectors. When Dave Smith performed this test on my truck, it was returning 240ml per minute, I believe they said 80ml in 30 seconds was acceptable, but can't remember for sure. They were pretty sure I needed all six injectors replaced..... (which they were going to cover on warranty) because I only had about 7k on my Formula1 injectors, I did not agree. We did agree to check the torque on my injector cross tubes first, they were all loose.



The second return flow test was around 100ml, the truck has started perfectly since.



Just a side note: Last summer my wife and I(and German Shepard) were on our way from Spokane to our place in Thompson Falls, meeting our daughter who was traveling from Helena, when my truck started stalling, as if shutting the key off and on. We were about 10 miles from Kellogg so I limped in to Dave Smith, never been there before.



They recognized our situation, put us to the front of the line. When their Cummins tech(Joe) saw under my hood(mods) we were called back to the shop area for a parlay(he also included their accessory/mod guru James), they allowed us in their shop the remainder of the day. We did two test drives(me driving) before and after, with their starscan connected to my truck, Like I stated, they were prepared to replace my injectors under warranty, regardless of my Smarty, Edge, TST, twins, etc. They treated us wonderfully, and I would highly recommend Dave Smith to everyone.

Oh yeah, the bill was 2 hrs labor!!!!



Sorry for my long windedness, Jess

 

[HBarlow]

If the injector cross tubes have fallen out of torque spec, that will directly affect rail pressure because they leak. I believe the ecm has to see 3500psi before it will allow the injectors to fire. The tolerance between the cross tube and injector body is so close that the difference between a cold and warm block could create this behavior.

If the cross tubes are leaking,the leaked fuel travels through a passage in the head to the return fuel line at the back of the head, it is not a visible leak. A high quantity return flow test on the injectors will identify a leak somewhere in the system, either a cross tube, cracked injector body, or leaking injectors. When Dave Smith performed this test on my truck, it was returning 240ml per minute, I believe they said 80ml in 30 seconds was acceptable, but can't remember for sure. They were pretty sure I needed all six injectors replaced..... (which they were going to cover on warranty) because I only had about 7k on my Formula1 injectors, I did not agree. We did agree to check the torque on my injector cross tubes first, they were all loose.

The second return flow test was around 100ml, the truck has started perfectly since.

Just a side note: Last summer my wife and I(and German Shepard) were on our way from Spokane to our place in Thompson Falls, meeting our daughter who was traveling from Helena, when my truck started stalling, as if shutting the key off and on. We were about 10 miles from Kellogg so I limped in to Dave Smith, never been there before.

They recognized our situation, put us to the front of the line. When their Cummins tech(Joe) saw under my hood(mods) we were called back to the shop area for a parlay(he also included their accessory/mod guru James), they allowed us in their shop the remainder of the day. We did two test drives(me driving) before and after, with their starscan connected to my truck, Like I stated, they were prepared to replace my injectors under warranty, regardless of my Smarty, Edge, TST, twins, etc. They treated us wonderfully, and I would highly recommend Dave Smith to everyone.
Oh yeah, the bill was 2 hrs labor!!!!

Sorry for my long windedness, Jess

That wasn't "long windedness", that was good information. I've never had an injector problem so didn't know all the details you posted.

Thanks. I am going to call my friend and suggest he or his buddy read all these posts in this thread. I believe the solution is contained here, just don't know which of you has identified it.

 

[HBarlow]

I think the injectors and cross tubes is a common problem for a long crank, but the OP suggested it would only start with a block heater (unless it was above 50 degrees). My limited experience (freely admit) tells me that a leaky injector will cause a long crank regardless of temperature. So the difficulty starting is more temp related than rail pressure related. We will probably find out that the leaky injector led to overcranking, wearing out his starter.

Your suggestion makes perfect sense to me. As I wrote above, I will suggest my friends read all of these posts themselves and consider all the suggestions. Thanks for your thoughts.

 

[MQuirin]

... He said they were going to send the truck owner down to a dealer in another town to have rail pressure read...

The engine will be warm after a trip and rail pressure readings may not tell you much. You need to see the RP when it's cold and won't start, then compare that to the RP after the heater is plugged in and the truck starts right up.