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Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 8412
Experience:  I am ASE Master Truck Certified.
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I just change The oil pump cause truck had a low oil

Customer Question

Hi, im Eduardo i just change The oil pump cause truck had a low oil pressure but still the same
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Cat Man replied 1 year ago.

Thanks for asking your question. I will try and help you out.

Does the yellow check engine light come on when the low power happens? Or low power and no light?

Customer: replied 1 year ago.
the yellow and red light
Expert:  Cat Man replied 1 year ago.

Thanks for the information.

Use the following procedure to retrieve the flash codes from the check engine light:
Turn the ignition key switch to the On position/ Engine OFF.
Turn the cruise control ON/OFF switch to the OFF position.
Move the SET/RESUME switch to either position. Hold that position until the yellow lamp begins to flash.
The yellow lamp will flash in order to indicate a two dijgit flash code and the SET/RESUME switch may be released. The sequence of flashes represents the system diagnostic message. Count the first sequence of flashes in order to determine the first digit of the flash code. After a two second pause, the second sequence of flashes will identify the second digit of the flash code.
Any additional flash codes will follow after a pause. These codes will be displayed in the same manner. Flash Code 55 indicates that No Detected Faults have occurred since the ignition key switch has been turned to the ON position.

Let me know what two digit code you get and I can tell you what the problem is.

Customer: replied 1 year ago.
The mechanic plug the computer and show low injector pressure
Expert:  Cat Man replied 1 year ago.

I see. Thanks for the information.

There are four things I have seen cause this.

The first and most common is a faulty heui pump. Which I believe you have replaced.

Second is a low oil level. A low level can allow the pick up tube in the pan to suck in air while driving and cause this code.

Third is a faulty injection actuation pressure sensor. It has three wires and is located on top of the engine near the front.

Lastly is a leaking injector.

Please reply back if you need more help or have more questions. I am happy to assist.

Customer: replied 1 year ago.
Hi.. I check the codes of the flashlights I think is 39 the two digit code
Expert:  Cat Man replied 1 year ago.

Thanks for the information.

Code 164-11 (39) is defined as an Injection Actuation Pressure System fault. I see this a lot on these engines. This code indicates the ECM is not seeing the correct Injection Actuation Pressure. This code and problem is caused by several things.

The first and most common is a faulty HEUI pump. To test a high pressure 5000 psi gauge is needed to connect to the outlet of the HEUI pump.
Second is a faulty IAP sensor. To test you can install a high pressure gauge into the head and compare the reading to a service tools reading.
And lastly is a leaking injector.

Please reply back if you need more help or have more questions. I am happy to assist.

Expert:  Cat Man replied 1 year ago.

Hey. I just wanted to see how things were going. Please let me know if you need more help. I am happy to assist. If my information was helpful, please leave a good or higher rating so that I receive credit. Thanks.