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Topic: ISX 15 Turbo boost drops (Read 432 times) previous topic - next topic

ISX 15 Turbo boost drops

I have a 2010 Phenix with the 650 hp ISX 15.  When I purchased the RV, the original owner replaced the turbo but not the turbo actuator.  I have since replaced the turbo actuator.

My problem is on long uphill grades, my turbo is boosting well, but out of the blue it drops all boost.  After the boost is dropped, it takes about 3 minutes and the turbo slowly begins to boost back up to normal.  It never happens on flat ground, even if it was a long passing spot.
It doesn't happen on all big climbs. Boost doesn't go over 44 lbs.
With its random happenings, I can't pin point why. 

I'm about to give up and put a none variable turbo on.

Re: ISX 15 Turbo boost drops

Reply #1 –
With your description and with that engine it may just be the ECM shedding some of the load due to the exhaust gas running too high. You may just need to be proactive and manually downshift the trans. (before it decides to down shift) and (in old horse terms ) give it's head.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: ISX 15 Turbo boost drops

Reply #2 –
Interesting, I will look into a bluetooth pyrometer gauge or see if its on my glass dash board.
Thank you, I'll look into it.

Re: ISX 15 Turbo boost drops

Reply #3 –
In my coach there is almost always boost, even at idle. When this happens on the climb and you lose all boost do you just stop dead in your tracks?

I have 600 hp and never seen more than 39 psi.

Mike's answer sounds very reasonable.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: ISX 15 Turbo boost drops

Reply #4 –
On a long hill, when the boost gets dropped, the boost goes to 0.  The RV then gets down to 20-30 mph for 2-4 minutes then slowly builds boost back up.  It will take about 1-2 minutes to get back to full boost. I've tried to drive with less than 40 lbs of boost and that doesn't seem to help much.

Re: ISX 15 Turbo boost drops

Reply #5 –
Are there any DTC's? 

Re: ISX 15 Turbo boost drops

Reply #6 –
Quote from: chris von ravensberg –
Are there any DTC's? 

I'm disappointed I didn't ask that question earlier. Your Silverleaf Dash should be able to show any, even if they cleaned
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago