Cat engine operation question

[Robin Goffrier]

We are transiting from BEND, OR to our lot in Indio, .CA. second leg of 3 took us from Sparks, NV to Ridgecrest, .CA. were in the mountains near Mammoth at about 7,800 ft elevation. Pulled into rest stop for a 15 minute break. Shut down engine. Fired back up and took off, continuing to climb. 20 seconds in rpms dropped in half, then immediately recovered. Three times in quick succession then recovered and ran like a top. 200 more miles and no issues.  Any thoughts? Could elevation have played a part? Thanks. It's a C9S 425 turbo. Been reliable to date.

[Keith Moffett]

Perhaps it was trying to derate which it does at excess temps.  How hot was it and possible a faulty sensor?

[Joel Ashley]

Check your coolant expansion tank.  If a leak somewhere dropped the coolant level below the sensor in the tank, or just even with it, it (among other conditions) can cause the engine to derate, especially on hills where the coolant level gets tilted a bit.  The back and forth of the fluid level over the sensor could cause the intermittent derate.

Just one easy place to check first, Robin.

Joel

[Keith Moffett]

Good call Joel.  Simple fixes first.   

[Mike Shumack]

Doesnt the "engine warning" light come on with a derate condition?

[Gerald Farris]

Robin,
Mike has a point in that if you were getting a derate condition, it should be accompanied with a check engine light, but a partially restricted fuel filter can cause the condition that you described without a check engine light. When climbing under a hard pull, the engine uses more fuel and a partial restriction can cause fuel starvation, but no fuel starvation on the down hill into Indio.

Gerald

[Dave Atherton]

Robin, you indicated you were pulling long grade,and engine in a derate low power. Depending
What the problem is , if your engine temperature is high you will have a code of 173-00 or
173-11 event code that will derate your engine and the check engine light will not come on.
Breaking out these event codes the first code will derate engine power 4 % and the second
event code will derate your engine by 8 % and the check engine light will not come on. These
two event codes are caused from a lugging of the engine on steep grades and there is no
maintance or parts to replace. The reason for the derate on power is to allow engine ECM to
adjust engine power for heat level without doing damage to engine. Last note: I just answered
last week for Ask Dave to Steve Huber the same event codes 173-00 and 173-11 breakout.
Dave Atherton Retired Cat Mechanic

[rick Kirchner]

Stop by the Indian Well Brewery on 395 before you pull into town.  It's in between the 395 and 178 intersections. 

[Bob Bulot]

Good recommendation, Rick!  Stopping there may not do anything to improve his Cat’s performance,  but at least, if he stays there long enough, he won’t care anymore!😄

[Robin Goffrier]

Thanks for all the input guys. Over the next 400+ miles no issues. However I have a further situation that may or may not be related. About 6 hours prior to my aforementioned engine hickup I got a yellow "check engine" light. I get them now and then and have always had a cat store run the diagnostic. It's never been anything that's even required attention and they told me that if its yellow, as opposed to red, just keep going. And since we were miles and miles from any community of consequence,  that's what I did. Often, after a certain period  of time the yellow alert shuts itself off, but not this time. I called cat and beaver. Basically, I'm on my own. I hit the diagnostic readout button and got "ENG D1-A9" CAT said it means nothing to them. 2 questions. Has anybody any idea what the diag reading means? And, any referrals fo qualified diesel engine diagnostic work in the palm springs/Indio area?

[Robin Goffrier]

Follow up question. I called Beaver Coach, where the coach was purchased, asked how I determine what the diagnostic code means. "Call the instrument manufacture ". Who is that?  Don't know. Anybody know who made the center console diagnostic readout instrument for the c9s?

[Joel Ashley]

Robin, not sure how you got “D” or “A” in your ciphering.  Aren’t the code flashes translated as numbers?  If so, no wonder CAT couldn’t proffer an interpretation.

The codes are online.  Any one engine may not have certain codes, but the numbers represent the same fault across most engines... the ASE saw to that to make life easier for techs.  So if you spot a familiar code number on another engine’s list, it will represent the same for your engine.

Not being experienced much here, I’ll leave the analysis to Dave.  Have your serial number ready for him, if you haven’t supplied it already.

Joel

[Dave Atherton]

Gentleman, Caterpillar has different codes for different engines and the engine codes in most cases, are broken out with 3 different values for each Code present. Example, 102-2, 102-4 and last 102-7
these codes are for boost pressure and are what is called. Mechanical code. Now the same boost
pressure sensor has what is called a electrical code like 32-05 32-4 and 32-11 understanding the
meaning is kind confusing and many sensors are changed out where nothing wrong with them.
Yes, you can find on the internet Caterpillar engine codes and that just adds to the confusion.
The engine codes breakout with the use of caterpillar diagnostic tool called Cat ET will take a person
to the problem. To some  may disagree and yes that is your choice but cannot explain engine
codes in any other form other than Cat ET. The blink codes are very limited and again is not the same
codes for different engines. Ask Dave can break out any and all caterpillar and Cummins engine
codes for our members. Last in closing. Reason for posting engine serial numbers with problems
on the forum . Example engine serial number 1WM tells the engine model 3126 A another serial
number CKM tells the engine model 3126 E the rest of the serial number will tell the build date,
engine arrangement number 210-4225 and engine specs. What all this means it is very important
information that can connect technical advise to the correct engine that will different from one
Cat 3126 A model to a 326 E model. Again factual technical information depends full complete
engine serial number. Dave Atherton Retired Cat Mechanic

[Robin Goffrier]

Thanks Dave,  The thing I don't grasp is how does the average coach driver get the code? My coach. With a C9s sends a code to the dash moniter but that's not what I get. Appearantly it's a code specific to the monitor. I called Peterson Cat and gave them the code my coach read and was told it was not a cat code. I called Beaver coach Sales service department and was told to contact the instrument maker. Ok, who is that? Don't know and I'm busy. So here I sit. Do you know if non cat dealers can access the cat electronic read outs?

[Joel Ashley]

Okay, I may be out of my league here because I’ve never had to concern myself with checking a diagnostic code.  But if I’ve got this right Robin has a dash component (button) that provides a code he believes relates to the engine.  I’m not privy to what that device is and perhaps others here aren’t either, apparently much like the providers he’s consulted.

My understanding has always been that the engine fault codes (albeit not as complete as a tech with the CAT ET diagnostic Dave alludes to) is available on the Allison transmission screen.  Robin, are you sure the button and readout you are using is for what you think?  To eliminate any chance of some misunderstanding, perhaps you could provide us with a photo or two so the issue of identifying it might be expedited.

That said, though some here are encyclopedias of component knowledge, it’d be entirely possible no one is familiar with the manufacturer of a 2008 Contessa’s console instrumentation module.  Or is it an Aladdin or Sony or other monitor unit?  As to that regard, perhaps REV Group’s Monaco division can assist.  Or try these guys:  http://www.custominstrumentpanels.com/monaco.htm

Joel

Also in case you don’t already have a similar reference, with code links:  http://www.rvtechmag.com/tech/82_faultcodes.php