ISC 350 Stop Engine Light

[relipp]

I have a 2000 Dynasty with an ISC350. My stop engine lights comes on and I lose boost down to 15lbs! I Change fuel filters (old ones were clean) and I can get it to start with ether. It will do 65 on flats but drops to 45 on over passes. I’m in Biloxi

[Dr4Film]

I don't think diesel engines are designed to be started with ether. In fact I remember seeing a sign in the engine compartment of my Windsor stating NOT to use ether to start the engine. I believe it has to do with the air intake manifold heater grids used to preheat the air. Using ether could cause a major explosion.

Why did you need to use ether to get the engine started initially?

What is your maximum boost when climbing a fairly steep grade?

Speed up a grade has little to do with anything. I climbed a grade in Jasper NP where I was doing 12 mph the entire 3 minutes while climbing however, I watched the rpm's so they were around 2000, I watched the temp of the exhaust manifold to make sure it didn't reach 1250F as my engine will de-rate then (less fuel) plus I also watched my boost to make sure it was at maximum boost while climbing.

If you are not getting maximum boost when needed then there is an engine problem either with fuel delivery (CAPS System) or your turbo.

Disclaimer - I am not a diesel engine expert. That's why when I have most engine problems I take it to the experts who do have the knowledge and expertise. I use only one diesel shop that is local to my home but when on the road I will only trust major truck repair places to work on my engine. No fly-by-night mechanics will touch my engine.

[Upsman85]

My 400 isl had a boost reference sensor go bad and would not make boost! I replaced sensor and all was well. 

[dholden_us]

I have same ISC, it is running derated to protect the engine.  My engine had a similar issue and it was the fuel valve suppressor that prevents damage to the ECM.  I would have it scanned and not drive it as you could damage the ECM

[vanwill52]

23 hours ago, relipp said:

I have a 2000 Dynasty with an ISC350. My stop engine lights comes on and I lose boost down to 15lbs! I Change fuel filters (old ones were clean) and I can get it to start with ether. It will do 65 on flats but drops to 45 on over passes. I’m in Biloxi

Richard is correct about not using the ether for starting.  And he was correct about the reason--there are powerful, high-amperage grid heaters in the intake manifold to aid in starting in very cold weather.  I can't verify this from personal experience, but it is my understanding that by the time the "Wait to Start" light goes out, they are glowing red.

On iRV2 there is a post about a fellow who took his coach to a CUMMINS facility and a novice mechanic used ether for some reason.  The resulting explosion caused enough damage that a total rebuild was required.  Luckily, Cummins owned up to it and did the repair without charge.  If an engine DOES NOT have intake grid heaters it is certainly a common procedure to use ether.  In your case, it is very dangerous.

There are several reasons the engine will de-rate after the Check Engine light comes on.  It would be best to have the engine codes read before continuing so that you have a better idea of the cause.  I hope you are luckier than me.  My problem was a faulty ECM.  VERY expensive repair.