Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Caflashbob on July 19, 2020, 01:06:48 am

Title: Stop engine light
Post by: Caflashbob on July 19, 2020, 01:06:48 am
Had a weird one happen today.  100 miles after filling the coach cruising along a warp 6(78) tach at 1680 or so and the stop engine light came on and the buzzer.  Started to slow.  Slight roughness when accelerating.  Never shut down. Just buzzer and light.

VPMS said everything perfect.  12 miles from end of my 500 mile  day. After a mile or so the light and buzzer went off.

Never stopped.

40k miles of solid reliability in 8 years.  And I use all of the capabilities of the chassis/coach.

Tough product. 

Is there a  oode reader built in?  I think there is....

Anyone read their m11's codes.

All fluids and filters are fresh.

Seems to run fine afterwards.  96 degrees outside.  Engine at 185 and trans at 208.

Coach has run lots of thousands of miles driven exactly this way.

But maybe not as long a straight stretch at speed.

This motor is made for 80k pounds. Overkill capacity in my experience.

Racks been run. Valves adjusted.

Fresh 125 gallons of fuel.  Can the fuel get hot enough to cause any issues in 120 miles?

And then go away.
Title: Re: Stop engine light
Post by: amos.harrison on July 19, 2020, 08:51:15 am
I use a Cummins Road Relay 4 instead of the VPMS.  I CAN access M11 fault codes directly, so they are certainly available but only by a Cummins computer.
Title: Re: Stop engine light
Post by: Caflashbob on July 19, 2020, 09:23:04 am
Brett where was the wiring to plug that into in your  coach?
Title: Re: Stop engine light
Post by: bbeane on July 19, 2020, 09:23:55 am
Ever done your fuel lines?
Title: Re: Stop engine light
Post by: Caflashbob on July 19, 2020, 09:27:07 am
Yes but maybe missed the aqua hot ones.  At that time 8 years ago I was not so sure everyline needed replacement.

Good point.  Thanks
Title: Re: Stop engine light
Post by: cdm on July 19, 2020, 09:38:06 am
My engine lights and buzzer have come on three times. Two times it was the isolator going bad and voltage very erratic. I worked around this by bypassing the isolator until I could replace it. 3rd time when I blew a turbo boot-this episode was accompanied by a lot of black smoke and loss of power.
Title: Re: Stop engine light
Post by: Jack Lewis on July 19, 2020, 09:42:54 am
.....
 tach at 1680 or so and the stop engine light came on and the buzzer.  Started to slow.  Slight roughness when accelerating.  Never shut down. Just buzzer and light.
VPMS said everything perfect.  12 miles from end of my 500 mile.....
And then go away.

I remember in Detroit diesel training they reported as many as 70-80% of stop engine codes being a false positive.  That was their reason for going to a gps and phone system to a tech for over the hwy truckers.  In their experience most of these error codes were due to a defective sender, or a bad ground.  I hope your error, is similar, you are able to correct, and code shows up when your able to get a reading.
Title: Re: Stop engine light
Post by: Pierce & Gaylie Stewart on July 19, 2020, 11:22:20 am
Bob,

Check your fuel pressure when accelerating. A restriction shows itself first when accelerating as this is the time your engine is using the most fuel. I usually can feel it when going up an on ramp onto the freeway. You probably have fuel pressure on your VPMS.

Pierce
Title: Re: Stop engine light
Post by: amos.harrison on July 20, 2020, 12:15:35 pm
Bob,
The Road Relay plugs directly into the Cummins diagnostic plug under the dash.
Title: Re: Stop engine light
Post by: Caflashbob on July 20, 2020, 05:42:45 pm
Intermittent ECM heat related failure.  41 times the stop engine light and buzzer displayed. Shop  ohmed  the injectors.  All good.  Like the scarecrow said I need a brain.  Why such a fine piece of technology wears out after only 23 years and 3,000 hours of careful abuse is beyond me.

Hot running is my suspicion.  Cooled by engine oil.  I think my feb 97 built coach has the fuel cooler on it.

Long history of Arizona use.

We got 800 hours and 40k miles ourselves and 8 years use. 

Part of the natural beauty of the vehicle. 

No reman.  Want and need ultimate reliability.  If it makes it another 3,000 hours then it's a probably a dollar an hour or so.

They are clicking the calculator keys.  No final numbers yet.

I was pretty sure the heat related  nature of the warning and missing and the progressively worsening failure was the brain.

Ran perfect cold at the shop this morning.  We have not really heated this up in the last few years.  High speed and hot fuel from the tank finally got the brain.

Rare failure here I think.  But most owners do not have a deserted coach driven fully for over 20 years?  The reference was to desert use.  Not deserted.
Title: Re: Stop engine light
Post by: Pamela & Mike on July 20, 2020, 06:06:39 pm

 What is cooled by engine oil?

Mike
Title: Re: Stop engine light
Post by: Pierce & Gaylie Stewart on July 20, 2020, 06:25:25 pm
Bob meant to say fuel cools the ECU. Easy mistake to make when typing posts. If it were not for spell check, no one could read my posts. Detroits also have fuel running through ECU. Good to have a cooler installed like Brett did. Our tanks are not cooled by air flowing by so the fuel gets hot. Perhaps too hot.

I just answered a PM from a member who wants to order an ECU out of China. They supply Cummins with a lot of OEM parts. $700 to almost $800 delivered by ocean freight depending on how many you want.  Original ISX15 QSX15 Electronic Control Module ECM 3408440 3408426 3681405 Since he may order a few, I will let him post details.

Bob, be aware that a wiring short between the ECU and the injectors can fry the ECU and the harnesses are not immune to failure. Also, on some models, an injector failure can damage the ECU.

Aftermarket parts rubbing on the wiring can get through the harness. Not a bad idea to order up a new harness to go with the ECU but the Cummins shop should be up to date on that.

Pierce
Title: Re: Stop engine light
Post by: Pierce & Gaylie Stewart on July 20, 2020, 07:00:52 pm

Ran perfect cold at the shop this morning.  We have not really heated this up in the last few years.  High speed and hot fuel from the tank finally got the brain.
/quote]
Since it ran perfectly to the shop this morning, are you SURE it's not fuel starvation that is causing the ECU to throw a code? That's a  classic sign. After sitting all night, the engine will run fine for a while until the debris gets stirred up and restricts the flow so the ECU produces a code. I've had this happen a dozen times on customer's MBZs. This repeats itself after sitting for a few hours or overnight.

Pierce
Title: Re: Stop engine light
Post by: Caflashbob on July 20, 2020, 10:13:57 pm
You are correct.  Fuel not engine oil.  35 year diagnostic guy checked the wiring and injectors.  They normally send the box to Cummins in Mexico for a rebuild.  Mucho dollars.  We are leaving the coach and driving home.  I asked them to try  to find a new ECU. 

Will drive or fly back to pick up coach