power loss on my Allegro

[foo-lin-yu]

Hi, Im new to this forum and would like to see if anyone has experienced a problem like I've been having on my bus. I have a 2008 Allegro Tiffin [Fred], 300 cummings. While driving, the bus will loose power anywhere from three to fifteen seconds then come back in. It just goes to idle then comes back. Its happened on hills up and down, on flat roads, out on the highway and in town traffic. I've taken it to freightliner on three different occasions and they can't figure out whats happening. Its there now and awaiting a call back from a factory rep. Any help would be greatly appreciated. FOO!

[Gary RVRoamer]

Sounds like a fuel delivery problem, most likely just a partially clogged filter. The other possibility is a clogged or leaky fuel lift pump that fails to supply adequate flow of fuel through the lines to the injector pump. The lift pump usually has a screen over its intake and that can get clogged if the tank is dirty or has an algae growth.

[J Walker]

It could be a fuel problem, but the dealer should know about that already. Also, a code should have been set and the dealer should be reading that. A code will direct you toward the problem be it electrical or fuel. I would expect a dash light to come on also when this happens.

[RV'nOldTimer]

Quote:

Originally Posted by foo-lin-yu Hi, Im new to this forum and would like to see if anyone has experienced a problem like I've been having on my bus. I have a 2008 Allegro Tiffin [Fred], 300 cummings. While driving, the bus will loose power anywhere from three to fifteen seconds then come back in. It just goes to idle then comes back. Its happened on hills up and down, on flat roads, out on the highway and in town traffic. I've taken it to freightliner on three different occasions and they can't figure out whats happening. Its there now and awaiting a call back from a factory rep. Any help would be greatly appreciated. FOO!

I've recently been through similar but not identical problems with the 5.9L 300 Cummins. Did your "check engine" light come on? If so, the dealership should get a diagnostic readout.

If your setup is the same as mine, there are three things I'd check. First the fuel filters, next the fuel tank vent for a stoppage and then the lift pump pressure. BUT surely the guys working on your unit have already done these things, right?

JT

[foo-lin-yu]

thanks guys for getting back so quickly. Before my last trip I had had a complete service and they had changed all fuel filters . They believe the problem is electrical but are baffeled because there was no error codes on the computer which I would think would rule out an electrical problem? I needed to pick up my bus today as my son was taking it to Texas for two weeks. They were still waiting for the factory reps to get back to them so I told them I would bring it back. I'll call my service rep and ask him about the filter screen and if they had checked the vent but Im pretty sure they had cuz they are a freightliner service center. I'll let you know what happens. Foo.

[J Walker]

The dealer can plug in a monitor which you can take with you and record the problem when it happens on the road. The current monitoring and recording of nearly everything by the engine ECM leaves me amazed that this is not found there somewhere. Maybe you could ask the dealer what in NOT recorded that might cause your problem and then look there. There is not much that the ECM does not record.

[GeoSKlak]

Sorry it took this long for me to find this posting but we were on the road.
I brought my 07 Allegro Fred to Freightliner and also Cummins for service and neither of them knew about the second fuel filter which is on the frame just behind the driver side rear tire.
That may be your problem.

[dajudge]

If the dealer gives you the run around, call Tiffin Industries and try to talk to Bob Tiffin, he is the man to talk to. I guarantee youwill get results in a hurry.