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Ask Cat Man Your Own Question
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 8426
Experience:  I am ASE Master Truck Certified.
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Eat one JA: We'll do all we can to help. Tell me a bit more

Customer Question

eat one
JA: We'll do all we can to help. Tell me a bit more about what's going on so the Heavy Truck Mechanic can help you best.
Customer: my up is down
JA: Anything else I can tell the Heavy Truck Mechanic before I connect you two?
Customer: I have a code for fuel actuation pressure. Pid 164 fmi 3. I would like to know the electrical test procedures. my injectors are not opening up. losing no fuel pressure on the hand primer pump. Cat 3126b
JA: I'm sending you to a secure page on JustAnswer so you can place the $5 fully refundable deposit now. While you're filling out that form, I'll tell the Heavy Truck Mechanic about your situation and connect you two.
Submitted: 8 months ago.
Category: Medium and Heavy Trucks
Expert:  Cat Man replied 8 months ago.
Thanks for asking your question. I will try and help you out.
Code 164-3 is defined as an injection actuation pressure sensor open circuit. This code is pretty common on these engines. There are three things that can cause the code.
Most common is a bad sensor. It has three wires and is located on top of the engine near the front.
Second is a faulty engine harness
Lastly is a faulty ECM. It's very rare for an ECM to cause a 164-3.
To troubleshoot. Disconnect the sensor. Then use a jumper wire or paper clip to connect pins B and C of the harness. If the 164-3 changes to a 164-4. Open to a short. The sensor is bad. If it does not. It's most likely a harness problem.
Please reply back if you need more help or have more questions. I am happy to assist.
Expert:  Cat Man replied 8 months ago.
One more thing. Also make sure you have 5 volts on pin A of the harness.
Expert:  Cat Man replied 8 months 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.

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