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Topic: Won’t start after changing fuel filters (Read 3242 times) previous topic - next topic

Won’t start after changing fuel filters

This morning the coach started right up but after a few minutes began sputtering and died. I thought the problem might be the fuel filters, so I changed both. Now it just turns over but won't start. I still think the original problem was the filters. Any ideas on what else I should try to get it going?
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #1 –
Do you still have the old pre-filter system?  If so, sucking air?  WINN 300200 pre-filter
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Won’t start after changing fuel filters

Reply #2 –
Quote from: Michelle –
Do you still have the old pre-filter system?  If so, sucking air?  WINN 300200 pre-filter
This is what I have.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #3 –
I'm not sure of your fuel system but on my 8.3 even after prefilling both my filters I will still have to manually prime my 8.3  3 to 4 times before it picks up and continue to idle even with holding the throttle open. Some are more finicky than others.
Dub McBride 1996 270

Re: Won’t start after changing fuel filters

Reply #4 –
Speculating that you have a "prime by using the electric fuel pump" engine. At least, my 2003 Cummins ISL did.

To prime:

Turn key to first position and listen for the fuel pump (best if you are at the back right side of the coach while someone else turns the key from off to first position.  Pump should run for 20 or so seconds.

If high RPM, it is pumping AIR. If so, repeat ignition off, first position... until pump RPM drops (fuel= lower RPM than air).

Be aware that leaks at the fuel pump are very common on this vintage engine.  Perhaps minor fuel leak when sitting, but big time sucks air when pumping.

Please let us know if this is how your engine works.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Won’t start after changing fuel filters

Reply #5 –
A forum member walked me through bleeding the system. I am getting fuel at the cylinder head on all cylinders, but it still won't start. I am calling it a day and will take a fresh look in the morning.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #6 –
I imagine your engine is a computerized engine so it could be a  sensor. Have you got any
way to get codes. 
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Won’t start after changing fuel filters

Reply #7 –
Since install of my FASS system i have to lite bleed at the pressure sensor on the caps pump.... mine will run but throws a fuel control system code until i lightly burp it...may be similar sensor on yours.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: Won’t start after changing fuel filters

Reply #8 –
I'd check that the engine ECM has power. Cummins engines are pretty simple on the start requirements, Power to the ECM and get it to spin and it does the rest. Is your check engine light or wait to start light working? Are you seeing any RPM on the tach when cranking? If you are getting fuel to the injectors, the next thing to check is that the ECM is working and actually firing the injectors.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Won’t start after changing fuel filters

Reply #9 –
Quote from: kgrover –
I'd check that the engine ECM has power. Cummins engines are pretty simple on the start requirements, Power to the ECM and get it to spin and it does the rest. Is your check engine light or wait to start light working? Are you seeing any RPM on the tach when cranking? If you are getting fuel to the injectors, the next thing to check is that the ECM is working and actually firing the injectors.
The check engine and wait to start lights are working. I do see rpm on the tach when cranking. I have the Blue Fire device and it has given me the code shown in the attachment a number of times, but the last several times I tried to start it did not give me the code. One time I saw several codes under inactive codes, and two were fuel system codes. Unfortunately I did not save them, but one had to do with the fuel controller or fuel control module.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #10 –
Cummins SPN 629 FMI 12 is an ECM problem.  Possibly low voltage:

Cummins SPN 629 - FMI 12 (Fault Code 343) - iRV2 Forums

So how is the voltage when cranking and have you tried using the boost switch?
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Won’t start after changing fuel filters

Reply #11 –
Quote from: Michelle –
Cummins SPN 629 FMI 12 is an ECM problem.  Possibly low voltage:

Cummins SPN 629 - FMI 12 (Fault Code 343) - iRV2 Forums

So how is the voltage when cranking and have you tried using the boost switch?
The voltage is showing 14.3 in the Blue Fire App. I have tried the boost switch. I am trying to locate the ECM now to check the connections.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #12 –
Quote from: dbennett9 –
The voltage is showing 14.3 in the Blue Fire App.
I seriously doubt that your start batteries show 14.3 volts while cranking.  The Blue Fire app may be reading coach battery volts?

If the Blue Fire voltage does not drop when cranking with boost switch activated, I would suspect boost solenoid is inoperative.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Won’t start after changing fuel filters

Reply #13 –
Quote from: Chuck & Jeannie –
I seriously doubt that your start batteries show 14.3 volts while cranking.  The Blue Fire app may be reading coach battery volts?

If the Blue Fire voltage does not drop when cranking with boost switch activated, I would suspect boost solenoid is inoperative.


Sorry, that was not the voltage while cranking. While cranking it drops into the 10.5 range.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #14 –
I am always skeptical of two unrelated issues happening at the same time.

Electrical issue? Fuel issue (immediately after changing fuel filters)?

Have you used the electric fuel pump as I described above to purge air?  Did the RPM/sound of the pump change as air was replaced with fuel??

Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Won’t start after changing fuel filters

Reply #15 –
Quote from: wolfe10 –
I am always skeptical of two unrelated issues happening at the same time.

Electrical issue? Fuel issue (immediately after changing fuel filters)?

Have you used the electric fuel pump as I described above to purge air?  Did the RPM/sound of the pump change as air was replaced with fuel??


I am also skeptical of coincidences. I did try the pump as you described. I am not certain of the sound change, but I also bled the injector lines individually and got good fuel flow.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #16 –
Quote from: wolfe10 –
I am always skeptical of two unrelated issues happening at the same time.

Electrical issue? Fuel issue (immediately after changing fuel filters)?

Per first post, the issue began before the fuel filters were changed:

Quote from: dbennett9 –
This morning the coach started right up but after a few minutes began sputtering and died. I thought the problem might be the fuel filters, so I changed both. Now it just turns over but won't start. I still think the original problem was the filters. Any ideas on what else I should try to get it going?

Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Won’t start after changing fuel filters

Reply #17 –
Quote from: Michelle –
Per first post, the issue began before the fuel filters were changed:


If the issue never was the fuel, do the symptoms (sputtering and running rough for maybe a minute before dying) seem consistent with an ECM problem?
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #18 –
What did the fuel in the old filters look like? It would take a lot of gunk to kill an engine "at idle". A lot less trash/water will cause one to perform under load poorly or even stop but to kill an engine at idle, we'll I will put it this way, I don't recall any of my heavy duty diesels ever not idle because of trash, run like crap and may not pull but 20 mph but die at idle I personally have not had that. Did my best to be clear with my words.immediately after a filter change all I said does not apply if filters were the issue.
Dub McBride 1996 270

Re: Won’t start after changing fuel filters

Reply #19 –
Quote from: Dub –
What did the fuel in the old filters look like? It would take a lot of gunk to kill an engine "at idle". A lot less trash/water will cause one to perform under load poorly or even stop but to kill an engine at idle, we'll I will put it this way, I don't recall any of my heavy duty diesels ever not idle because of trash, run like crap and may not pull but 20 mph but die at idle I personally have not had that. Did my best to be clear with my words.immediately after a filter change all I said does not apply if filters were the issue.
I don't think it looked terrible. I had another time when the engine began to run badly under load, losing power but never dying, and the fuel this time did not look as bad. There were dark particles in it, but not to the extent I saw the other time.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #20 –
That code means either the ECM is dead, or it has a voltage problem. The power to the ECM is on a 4 pin Deutsch connector going into the ECM. 2 power wires and 2 ground wires. I would take a look at that connector and make sure the connections are good. Might just be a loose wire going to that connector or a bad fuse for the ECM power.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246

Re: Won’t start after changing fuel filters

Reply #21 –
Quote from: dbennett9 –
If the issue never was the fuel, do the symptoms (sputtering and running rough for maybe a minute before dying) seem consistent with an ECM problem?

I would think if the ECM weren't functioning correctly, it would impact how it controlled the engine systems, including fuel delivery.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Won’t start after changing fuel filters

Reply #22 –
Do you have any idea where the ECM might be? I have looked everywhere I can think of but haven't found it.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #23 –
Just to help eliminate the possibility that I still have a fuel issue, I took one of the injector lines loose and used a tube to collect the fuel into a container. In ten seconds, it pumped 2 ounces of fuel, and that was after the what was in the line drained out when I took it loose. I have no idea whether that is normal, though.
Dave and Kathy Bennett
2004 U270
Build #6253
1600W Solar
700 AH Battle Born Lithium
2015 Jeep Wrangler

No matter what happens, remember you always get the trip out of it.

Re: Won’t start after changing fuel filters

Reply #24 –
Should be mounted on the lower part of engine block, just above where oil pan is bolted to the block. Often times on drivers side but could be opposite. I've had more series 60 Detroits than Cummins.
Dub McBride 1996 270