Engine Problems

[Brandy]

I was wondering if you guys have ever experienced this kind of problem. I drive a Freightliner Century 112 and about a month ago the truck just cut off on me as soon as I entered the parking lot of a truckstop. They had a 24 hour garage so I asked one of the mechanics to come and see what the problem was. After checking the truck up and down, he noticed that the fuses that connected the the battery power to the engine computer were blown. He changed them with a couple 20AMP fuses and the truck started right up. He thought that it might be a ground problem so he tightened down every grounding nut and bolt and also checked the battery connections and they were fine.

A week later the truck did the same thing, cut off on me when I pulled into a parking lot of a Wal-Mart. Same thing again, blown fuses, so I went into Wal-Mart and bought me some 30AMP fuses and then took the truck to my trusted mechanic Don at B and B Truck Service in Columbus, Oh. He checked the truck up and down and couldn't find anything wrong. So since the truck was acting fine I left and it ran good for about two more weeks.

Then I noticed that everytime I came off an off ramp or stopped at a stop light the truck would shut off for a split second and then come back on again and then go through its light checks and what not. I know what your gonna say "It Might Be Your Fuel Or Fuel Filter", but its not cause remember I'm now using a 30AMP fuse, and after a few attempts at trying to shut down, those fuses succumb to the same fate as the 20 and 25AMP Fuses. I have a Cummins M11 engine and am not having any problems while driving, only when (sometimes coming to a stop) and when stopped at a stoplight. The truck has plenty of Oil and the fuel filter was just canged 4 months ago. Any suggestions of what the problem could be before I take it into Freightliner and get screwed?????????????

 

[Weave]

There is a short occuring somewhere in that computer circuit. 20 amp fuses are hefty ones to be blowing, and putting bigger ones in isn't really the safest answer. I'll take it you have a M11 plus as it has electronic FI. This can be a few different things. First do the simple stuff- inspect and wiggle the power wires going into the engine module to make sure they aren't arcing to ground. I don't think that's the problem, but try anyway. It looks like the module itself is drawing too much current at the times when it is switching into idle mode. DO NOT go to Freightliner on this problem, go to a Cummins shop! They can hook the M11+ module up to a PC there and see what is up with it, it will have a history of what the fuel system has been doing stored in its memory. Cummins will get to the cause of the problem and the quickest and cheapest solution much faster than Freightliner can. Hopefully its something simple!
-Weave-

 

[Brandy]

Thanks alot Weave, what you said not only makes sense but your right, when the engine is slowing down from running, at a steady rpm thats when it wants to cut off. I'll take it to Cummins first thing Monday morning.

Sean

 

[streetsweeper]

In backup to Weaves answer. Check the negative ground terminal at the batteries AND the frame ground connector post. Do it yourself or have your favorie mech do it every oil change faithfully. Dis-assemble it, swipe several times all the way around with a small hand held wire brush.

Next, coat the connection AFTER your done putting it back together with moly grease.It will help protect against the rusting period. End of story.

When on the road and the mechanic says he cant figure it out, you will know what the cause & fix is.

 

[ole driver]

Brandy your problem could also come from a short to ground some where between the fuse and ECM. this must be corrected before bad weather comes,it will leave you sitting in the cold.
have your favored shop visualy inspect both leads good luck
ole driver;-)

 

[Brandy]

Thanks for the info guys. When I told the Owner of the Truck what Weave had said, he then told me that he had some work done on the engine computer. Turns out when he had the govenor removed they had to open up the computer box, remove a chip and they burned another one with some new info on it and then put the thing back together. I had the grouding checked twice and the battery cables cleaned till they shined like silver so I know its not that, and I had the ground wires checked to make sure they were nice and tight to the frame.

Sean