Author Topic: C9 Turbo problems  (Read 473 times)

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C9 Turbo problems
« on: July 02, 2019, 09:34:40 AM »
Hi there


I am dealing with importing and selling American Motorhomes to Sweden.

Started doing this after moving back to Sweden after a few years living in Ft Lauderdale.


We have a problem with a CAT engine most possibly never seen before in this country since the setup is motohome related for just a few years.


It is a 2008 Beaver Contessa with CAT C9 425 Hp variable pitch Turbo and regeneration system..


Problem is it is losing power when you floor the pedal, it is like just turning itself off, It feels like it was running on fewer cylinders or something like it.


You have to let go the pedal and come back easy to be able to continue. I noticed turbo boost at full power is some 32 PSI-


We just changed injector# 2 due to error code but now we have several error codes relating to the turbo and the actuator.


I hade a CAT guy out changing this injector and he got under the RV and disconnected the arm between the actuator and the turbo. Turbo parts move freely, no restrictions at all.


What can cause this problem??? CAT Sweden are not familiar with this so I am kind of lost here and need help.


Hope someone has some kind of input that helps.


Thanx in advance


Pete Sweden.

Offline ziggyh

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Re: C9 Turbo problems
« Reply #1 on: July 02, 2019, 12:25:51 PM »
Pete, Have you checked fuel pressure while under load and checked for air in the fuel return line.  Also, post what data you have like codes ect. may also be helpful in trying to solve your problem.

2007 Revolution LE


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Re: C9 Turbo problems
« Reply #2 on: July 03, 2019, 10:38:45 AM »
Hi and thanx for replying.

Well, I will have to ask the CAT service guy to check for these things you mention, me myself has no means to do this. Unfortunately the CAT man leaves for a vacation like a week or so now, so it will take some time before I can get him out here.
I will keep you posted.
Ps. I will also ask him to pull tje error codes which I will post hete


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Re: C9 Turbo problems
« Reply #3 on: July 20, 2019, 04:00:13 AM »
An update on the subjekt.

I drove this RV for some 4 hours to a place up north some week ago for a paintjob.
Now it ran like it should, uphill, no problem. Had up to 36 psi boost.
Yesterday I picked up the RV again to drive home.
Now I had 25 PSI at most and turbo feels like it is lagging, not very responsive when hitting a hill or flooring the pedal.
When driving it on cruise ctrl, it sometimes dont respond at all when hitting a hill, sometimes it does but slow to build boost.
A few times cruise ctrl was cut out.
Regen lamp lit up once, and service engoíne soon lamp also came on once.
To me it feels similar to having a turbo that are stuck more or less, but its not, we disconnected the arm to the actuator a few weeks ago and everything moves easily.

Anyone on this forum have any idea what to look for?
Have just one error code on dash with engine running, SPN641 FMI7
No error codes with engine shut off.
I know the CAT guy that came out to change one injector got more error codes with laptop plugged in and those were about Turbo and actuator.

Hope to get some input.



Offline David.e.atherton

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Re: C9 Turbo problems
« Reply #4 on: July 21, 2019, 04:32:13 AM »
Americanmotorhome turbo problems, The first you indicated you have a Caterpillar C-9
but as I was reading you have a Caterpillar C-9S with the regeneration system which is
completely different than a Cat C-9. The engine serial number is ever so important in
assisting with engine problems. Ok let’s go with the Cat C-9S regeneration system and
Your turbo problem.. there are several sensors related to the regen system and the turbo
charger and main problem area in almost all problems ( faulty sensor, excess heat within the turbo charger and the Regen ARD head ). Digging deeper would point first failed regents
Caused by a temp sensor ( 3 ) and the sensor that fails most is by the ARD head. Next
checking out the ARD Head itself has been a problem with cracking and is very expensive
Part to replace but this is the area where your problem is located. You need to take motorhome
to a Caterpillar service shop for your repairs and first connect Cat ET into engine Data port
which will pin point you into the area of your regeneration system and turbo charger . Your
DPF filter will be the first thing service shop will want to change but in most cases problem
Is not in that area. Ask Dave, Dave Atherton Retired Cat Mechanic