3126 cat goes into "engine protect" mode and does 45 mph??

Rolls Canardly again,
I am sorry - I did not get the whole story out there.
Coolant reservoir is full.
I took it in to Sherwood Freightliner in Dunmore, PA. to scan the codes.
They were going to call me when they got the two sensors in from Cat
to set up an appointment to fix this problem.
That's a week ago. Never heard back?
Had the "Top Secret" codes - so I went off the reservation.
"Injection Actuation Pressure" was the easy one, right on top.
The twin sensors behind the front cover, and behind air pump,
was the hard to access pair. Took awhile.

Actually saved half the price on sensors, so I am ahead there;
thanks to "New York Heavy Tractor's" excellent parts pricing.

If the codes were produced by the loss of returning feedback,
or no computer input from those two circuits, (however you want to say it)
and you were to replace the sensors, and it does not fix the problem,
all that is left is the wiring and connectors between sensors/computer.

I'm not licked yet; I will let you know if I find the issue in the ECU connector,
the connector between the Freightliner /Caterpillar harness, or wiring.

Rolls Canardly

 

Rolls Canardly here,
You are correct.
I did not call out a nomenclature on them.
Just swore a lot getting them in - poor design engineering.

"Injection actuation pressure" sensor is the easy one - on top of the head.
"Engine Speed Timing " is the one, (Pair of,) sensors you are speaking of.
No room to work and far enough in that you cant hardly see. Lots of fun!
Never changed one before - and that's the last one I'll change. Took 2.5 hrs!
(Yes, I know, you can take air pump off; "Mr. Diesel" on Answer.com said
you can do it without taking off the pump. he was right. But what a struggle.)

All I know is - I'm flying along the interstate about 80 and it suddenly drops anchor.
Almost got a truck up my ###. Several in fact. Not good.
And the other drivers wonder what the hell you are doing???
Thank you Caterpillar for protecting my engine. Tell it to my widow.

Rolls down one hill, canardly get up the next.

 

Rolls Canardly here,
Got both sensors because the "Dealer" scanned the truck, and those were what was throwing codes.

I went into depth about which sensors it was, and how "Dealer" wanted $430.00
and I got them from "New York Heavy Tractor" for half that.
"Dealer" was going to order two sensors and call me to schedule service.
That was a week ago.
Seemed like "Dealer" didn't want to be bothered fixing my truck.
I Pulled the Computer plug and cleaned it myself - with no result.
Gonna try Horwith Freightliner near Allentown and see if they have a better attitude.

Rolls down one hill, Canardly get up the next

 

Rolls Canardly here,
Tried the other close Freightliner Dealer and they diagnosed it as HPOP,
which they didn't have, for a total of 3000 bucks.
(Not much if you say it fast.)
I questioned if they checked the IPR valve, as they have an O Ring out on end
that can bypass, and just be dumping oil. "Have to wait until Tue. when tech is back."
ButI know the answer already. No pressure; YUP, your pump is bad.
The IPR valve mtd. to pump gets over 50 inputs a second from computer to manage oil.
I am hoping when I pull it out the O ring on end is split. Simple stuff first, right?

Would a Dealer sell you an oil pump with a new Injector Pressure Regulator Valve mounted to it for three grand when all that's wrong is a 20 cent O-Ring????

I am not one to "Take their word for it" and be at the mercy of someone who
holds the knowledge of how it works and what is wrong so close to the vest.

I play an entirely different game.
I let you know 110% - and you take and use the 45% you need. That's old school
This is another secret club; and you ain't in it.
God do I hate these fly by wire, computer controlled, overly unnecessarily complicated,
overpriced, top secret, sensor laden, de-rate for your safety ENGINES!!!

I scanned this download for Virus, Trojans, Worms, etc. and it's clean.
*free download For 3126 CAT - TM-9-2320-312-24-2 on liberatedmanuals.com*
shows good explanation of IPR valve at various stages of engine operation.

Codes I had were:
164-2: "change in press. not consistent with change in sensor current."
164-11: "actual press. and desired press. were different."

 

Thank you. Generous offer. (I need all the help I can get!)
I put brand new zero miles short block in from Cat. - not 25,000 miles ago.
Along with it, I put new pump and new injectors for extra 4000 bucks.
Got 14,000 bucks in just getting this up and running.
Pulled the receipts - and it was 2012!
Time flies when you're having fun!
So I guess pump could be bad; just hoping its only and O-Ring now.
You are too distant to make a trip to you at (sometimes) 45 MPH.
FEDEX or UPS would work for me - I can install.
I was born with nothing and still have most of it.

 

Hey Quality truck,
I have the same problem again with the HEUI pump.
Worked well all this time - but now rattles.
I wondered if you had any experience with taking these pumps apart?
I was going to see if I could take the good guts from mine that still makes good pressure
and put on the other pumps good shaft. I think the small bearings gone.
Call me (570) 269-6502
Thx,