"Stop" Dash warning light

[JoJam]

Yesterday as I started heading up over Mt. Ashland on I-5 Southbound I had a "Stop" light appear on my dash. Scaring the bejesus out of me, that's exactly what I did. I couldn't find an explaination for it either because of stress, or it just wasn't in any of my literature. There wasn't anything wrong according to my instruments and all my fluids were ok. It happened once more on the way to the top before I decided to creep up the hill. The slow crawl seemed to do the trick as I didn't have a problem with it the rest of the way up. Down hill and flat driving, didn't recreate the problem, but under normal driving conditions as I started up a hill and increased throttle pressure the light would come on. That's when I noticed that if I let off on the trottle pressure, the light would go off. I have a 2000 38ft. Monaco Dynasty with the optional 350 Cummins, 6 speed Allison. Can anyone explain what that light relates to and have any of you out there had a simular experience?

[krivanj]

The Cummins guy said it could be fuel starvation, low coolant, maybe something else (it was three years ago, and I do not own the RV anymore.)
I'm pretty sure it was listed in the Cummins ISC engine manual which came with the RV...

[kjburns]

My coach did the same thing from the very first trip. The dealer supposedly fixed it, but it reared its ugly head again on a long trip. On the way home it got worse, starting the warning on very slight inclines. Finally, it started on a flat road and I had it towed to Freightliner.

The problem was simply that the dealer had overfilled the oil.

[tiffinboy]

krivanj wrote:
To answer tiffinboy, yes, my stop engine light would come when I pressed on the accelerator, and go off once I released it slightly (going up hill). It was a Saturday, and I got hold of Cummins emergency network, but they wanted $700+ two hours minimum labor to open their shop in Savannah on a Saturday. I was about 100 miles from there. Talking to them and to Spartan Chassis, and reading the Cummins book, I stopped and checked my water/fuel separator. First time ever, nothing would come out of the petcock at the bottom when I opened it. I changed it and that fixed the problem.

did Cummins or anyone explain where the signal comes from? like what sensor activates stop engine lite to come on when fuel filter starts to plug up?
seems very hard to believe.I certainly could see it if the unit was surging and dieing out under heavy throttle but to run absolutely normal and full power seems odd.I would like to know how this system is activated for my personal book of knowledge if anyone knows please post answer

[tkcas01]

Well, you just saved a heck of alot of money! Always rewarding to be able to DIY!

[krivanj]

To answer tiffinboy, yes, my stop engine light would come when I pressed on the accelerator, and go off once I released it slightly (going up hill). It was a Saturday, and I got hold of Cummins emergency network, but they wanted $700+ two hours minimum labor to open their shop in Savannah on a Saturday. I was about 100 miles from there. Talking to them and to Spartan Chassis, and reading the Cummins book, I stopped and checked my water/fuel separator. First time ever, nothing would come out of the petcock at the bottom when I opened it. I changed it and that fixed the problem.

[JetAonly]

tiffinboy wrote:

JetAonly wrote:

tiffinboy wrote:

low coolant will make stop engine lite indicater come on

FWIW the low coolant sensor sets the Warning light.

what is your post about ?? I said low coolant will or may set off the warning lite?

:R

[tiffinboy]

JetAonly wrote:

tiffinboy wrote:

although I have never heard nor seen a dirty air filter set off the stop engine lite its easy to check the air filter indicater?if its sucked up to the top on the sight glass it needs replacing for sure
also if the fuel filters were that dirty the engine would show lack of power when the lite came on
DID? u happen to look at engine temperature at the time the lite came on? may be just low on coolant is all?low coolant will make stop engine lite indicater come on

FWIW the low coolant sensor sets the Warning light.

what is your post about ?? I said low coolant will or may set off the warning lite?

[JetAonly]

tiffinboy wrote:

although I have never heard nor seen a dirty air filter set off the stop engine lite its easy to check the air filter indicater?if its sucked up to the top on the sight glass it needs replacing for sure
also if the fuel filters were that dirty the engine would show lack of power when the lite came on
DID? u happen to look at engine temperature at the time the lite came on? may be just low on coolant is all?low coolant will make stop engine lite indicater come on

FWIW the low coolant sensor sets the Warning light.

[JetAonly]

tiffinboy wrote:

JetAonly wrote:
Typical of that vintage is a stop engine light for the ECM oil pressure sensor to fail. Mine did. It will intermittently report low oil pressure which will set off the stop light. The oil pressure to the dash gauge is a separate sender. Cummins has a fix. Changed the sensor to a low pressure switch, with a ecm update and a wire to an ECM pin. ~$500 total.

who knows? sounds reasonable to me but why only when hot pulling a incline at heavy throttle?

I thought mine was due to low fuel quantity, till it happened a week later with 3/4 tank. Could also be signaling lift pump going bad. They have seals that don't play nice with ULSD and end up leaking. ~$930.

Until you have the codes read we are all guessing. The cheap/easy fix is to replace the fuel filters and see if you still have the problem. The two filters are an FS1022 and a Racor S3201T on mine.

[tiffinboy]

krivanj wrote:
Mine on a Cummins ISC 330 was a plugged fuel filter. No loss of power but exactly your symptoms. I called Cummins, and they thought it might have been the filter, so I changed the filter and no more light, even with hard uphill pulls. When I got home 1000 miles later my mechanic said no codes stored.

so your fuel filter getting dirty but engine still ran normal and normal power made the stop engine lite come on??

[krivanj]

Mine on a Cummins ISC 330 was a plugged fuel filter. No loss of power but exactly your symptoms. I called Cummins, and they thought it might have been the filter, so I changed the filter and no more light, even with hard uphill pulls. When I got home 1000 miles later my mechanic said no codes stored.

[tiffinboy]

mgh122 wrote:

tiffinboy wrote:

mgh122 wrote:
Going up a hill low coolant, on level ground sensor reads ok, been there done that. Add a quart of coolant all is well.

ive it more fuel and the

Like I previously posted possible slightly low coolant when high RPM and circulating coolant harder.(possible senerio)

Sensor is in the top front of recovery tank, going up hill just barely covered, give it more fuel the rig accelerates and sensor is exposed.

yes and that's why I was suggesting low coolant sensor yesterday although on my unit 425ISL it simpley says low coolant warning

[mgh122]

tiffinboy wrote:

mgh122 wrote:
Going up a hill low coolant, on level ground sensor reads ok, been there done that. Add a quart of coolant all is well.

ive it more fuel and the

Like I previously posted possible slightly low coolant when high RPM and circulating coolant harder.(possible senerio)

Sensor is in the top front of recovery tank, going up hill just barely covered, give it more fuel the rig accelerates and sensor is exposed.

[tiffinboy]

JetAonly wrote:
Typical of that vintage is a stop engine light for the ECM oil pressure sensor to fail. Mine did. It will intermittently report low oil pressure which will set off the stop light. The oil pressure to the dash gauge is a separate sender. Cummins has a fix. Changed the sensor to a low pressure switch, with a ecm update and a wire to an ECM pin. ~$500 total.

who knows? sounds reasonable to me but why only when hot pulling a incline at heavy throttle?

[JetAonly]

Typical of that vintage is a stop engine light for the ECM oil pressure sensor to fail. Mine did. It will intermittently report low oil pressure which will set off the stop light. The oil pressure to the dash gauge is a separate sender. Cummins has a fix. Changed the sensor to a low pressure switch, with a ecm update and a wire to an ECM pin. ~$500 total.