Maxforce 7 turbo over 45psi check engine

[RETRO]

My 2011 Monaco Vesta’s Maxforce 7 gets a check engine triangle light and the power drops off for a code referencing the turbo manifold pressure is above spec at 45 psi. Turn the engine off then on and the code clears. Now I watch the Engine turbo pressure gage and sure enough the psi bounces up into the 40ies but kind of unstable up then down? Any suggestions out there? Any good Maxforce engine shop sudgestiing? Preferably in California but I’m open to USA

[arcaguy]

Have you called your local International dealer? They're the folks that made the engine.

[RETRO]

Originally Posted by arcaguy

Have you called your local International dealer? They're the folks that made the engine.

Thanks, seems it’s the only place to get help on the MaxForce 7 so I have an appointment next Monday

[Dandick]

Originally Posted by RETRO

Thanks, seems it’s the only place to get help on the MaxForce 7 so I have an appointment next Monday

Just checking to see if you got an answer to your problem. I have a 2012 Monaco Diplomat with Maxxforce 10. I have seen my boost go to 40-41 if I “put my foot in it”. I have no idea what the safest max boost is, or if the 40-41 reading is normal.
Dan

[RETRO]

Originally Posted by Dandick

Just checking to see if you got an answer to your problem. I have a 2012 Monaco Diplomat with Maxxforce 10. I have seen my boost go to 40-41 if I “put my foot in it”. I have no idea what the safest max boost is, or if the 40-41 reading is normal.
Dan

The MaxForce 7 normally has a max psi of 30 to 31 and with the 45 psi I get a triangle engine light and the computer goes into slow down mode to protect its self. The shop did a computer analysis and said I need a new turbo assembly. Nobody fixes these things they just replace parts. Id think the 41 psi on you MaxForce 10 is probably normal especially if your not getting any engine warning light. Mine is still in the shop, I just hope I get it back before WWIII starts. Good luck and stay safe!

[RETRO]

Got it back from the shop and it runs really good, a new twin turbo was installed and it has much more power. So here it is 9 months later and on my last trip the power seems less now and that damm triangle warning light came on climbing a hill and I lost all power (derating), I saw the boot jump to 40psi so now the boost doesn’t stop at 37 anymore. I pulled off and restarted the engine and the warning light went away thank God. I now constantly watch the boost and keep it in the below 40 range,,made it home safely but again I have lost confidence in my beloved Rig.

[craigd853]

Originally Posted by RETRO

Got it back from the shop and it runs really good, a new twin turbo was installed and it has much more power. So here it is 9 months later and on my last trip the power seems less now and that damm triangle warning light came on climbing a hill and I lost all power (derating), I saw the boot jump to 40psi so now the boost doesn’t stop at 37 anymore. I pulled off and restarted the engine and the warning light went away thank God. I now constantly watch the boost and keep it in the below 40 range,,made it home safely but again I have lost confidence in my beloved Rig.

Hello sir, that repair has to be under warranty and I'm sure it wasn't cheap to fix the first time. Take it back and have them fix the problem correctly. Good Luck

[Violin Guy]

Originally Posted by RETRO

Got it back from the shop and it runs really good, a new twin turbo was installed and it has much more power. So here it is 9 months later and on my last trip the power seems less now and that damm triangle warning light came on climbing a hill and I lost all power (derating), I saw the boot jump to 40psi so now the boost doesn’t stop at 37 anymore. I pulled off and restarted the engine and the warning light went away thank God. I now constantly watch the boost and keep it in the below 40 range,,made it home safely but again I have lost confidence in my beloved Rig.

I just joined site and read this post. I have a 2012 Vesta with this MaxxForce 7. My first lengthy trip shortly after buying it used in 2019 (with 75k miles)was a 5,000mi trip to Oregon and back from MI. When I encountered the first climbs on cruise and it downshifted, the CE triangle came on as you described, and would limit boost to 25psi. Which on a long 6-7% grade climb would pull the hill climb down to 35-40mph. Like yours it went away with a re-start and behave normally. I quickly learned that it occurred when the Turbo boost exceeded 40psi, so I would take it out of cruise and ease the throttle back as the boost rose to 39-ish. It manages the climbs satisfactorily with this "manual" control, but I don't like "work-arounds", and want it to perform as designed!
I had run across a thread somewhere that mentioned an adjustment to limit the boost pressure, and a re-adjust of that upper pressure limit would keep it from going into a "CE" condition.
I've driven mine 15k miles to date, and except for replacing a Mass Airflow sensor last month, and the above symptom, the MaxxForce 7 has taken us on many memorable trips at 11mpg (no DEF), and the exhaust regen has worked flawlessly.
Anyone with comments on boost adjustment would be curious to hear about...

[Hpozzuoli]

I have the same engine. Do not call international. Find a reputable third party shop…or come out to RI and go to my shop. I believe my shop will do an over the phone consult as well. They have maintained and fixed every issue I have had with my maxforce. They are very quick and affordable. They also know these engines in and out because they do a ton of small box truck and school bus work.

Send me an IM if needed. You might also consider joining the maxforce 7 Facebook page. It’s geared towards Tiffin breeze owners but anyone with a maxforce can join. There are some very smart folks on there that can help for free.

[RETRO]

After many over boost triangles and return trips to my mechanic, they finally replaced the Boost Control Solenoid (BCS) and no more over boost triangles!!! This seems to have been the problem all along, not expensive and a quick fix.