CAT Engine 178510 Fault Code: Intake Manifold Pressure Signal Abnormal Rate of Change
Also called Intake Manifold Pressure Sensor : Abnormal Rate of Change, Intake Manifold Pressure Sensor Abnormal Rate of Change, Intake Manifold Pressure Sensor abnormal rate of change, Intake Manifold Pressure Signal abnormal rate of change
Intake Manifold Pressure Signal Abnormal Rate of Change · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Code 178510 (SPN 102 / FMI 10) means the CAT ECM sees the intake manifold pressure signal staying abnormally steady, not fluctuating normally, for more than 30 seconds while the engine runs above 1000 rpm. The ECM sets the pressure value to a default (gauge pressure of zero) and logs the code. This affects C11, C13, C175, C27, and C32 engines.
Medium severity. The engine keeps running but loses accurate boost pressure feedback, which can cause poor acceleration and possible derate on some configurations. It is not an immediate shutdown code, but it should be diagnosed before it triggers other pressure-supply codes or masks a real turbo/intake issue.
What does CAT Engine error code 178510 mean?
Code 178510 is an FMI 10 fault, meaning the ECM expects the intake manifold pressure signal to fluctuate slightly as the engine runs, and it does not see that normal movement. The signal is either frozen, too slow to change, or stuck at one value for longer than the ECM allows.
The intake manifold pressure sensor is one of many sensors fed by the ECM's regulated 5.0 ± 0.2 VDC supply, routed through terminal 1 of the sensor connector, with sensor return on terminal 2. If the sensor itself fails internally, or if there's a wiring problem in the supply, return, or signal circuit, the ECM won't see the expected pressure variation.
When this code is active, the ECM sets the intake manifold pressure value to a default (gauge pressure of zero) and logs the fault. On engines with an electronically controlled wastegate, the wastegate solenoid signal is also forced to a default value. This intentionally limits boost to prevent turbocharger overspeed and intake overpressure, but it also causes noticeably weak acceleration until the fault is resolved.
What triggers a CAT Engine 178510 code?
The ECM sets this code when three conditions are all true: the signal voltage from the intake manifold pressure sensor is not changing at a normal rate for 30 seconds, engine speed is above 1000 rpm, and the ECM has been powered for 2 seconds. When the code sets, it is logged and the pressure parameter is forced to a gauge pressure of zero.
Common causes of 178510
- Damaged, corroded, or loose connectors and wiring at the intake manifold pressure sensor or ECM
- Internal electrical failure of the intake manifold pressure sensor itself
- Problem in the sensor signal circuit, including opens or excessive resistance between the ECM and sensor
- Problem in the sensor supply circuit (the shared 5.0 ± 0.2 VDC ECM supply feeding this and several other pressure sensors)
- Intermittent wiring fault, such as chafing, pinch points, or abrasion in the harness
- Faulty ECM if wiring and sensor both check out
How to troubleshoot CAT Engine 178510: first checks
- With the key off, inspect the intake manifold pressure sensor connector and ECM connector for corrosion, moisture, bent pins, or loose terminals
- Check the wiring harness between the ECM and sensor for chafing, pinch points, or abrasion, especially anywhere it runs near moving or hot components
- Verify the sensor is receiving its regulated supply voltage and that the return circuit is intact; remember this sensor shares its 5-volt supply circuit with several other sensors, so a supply-side fault can affect more than one reading at once
- Check for other active diagnostic codes on shared circuits (such as sensor supply codes) since a supply fault can trigger multiple codes together
- If wiring and supply check out, test or replace the intake manifold pressure sensor itself
- If the sensor tests good and wiring is confirmed intact, suspect the ECM
How the code clears
No separate clearing/reset procedure is listed for this code. Once the underlying wiring, connector, or sensor problem is repaired and the intake manifold pressure signal fluctuates normally above 1000 rpm, the ECM should stop logging the fault on subsequent operation. Confirm with a diagnostic tool that the code is no longer active and that stored/logged status clears per normal ECM behavior.
Affected models and serial ranges
178510 appears in our records across 5 CAT Engine models. Match your machine by model and serial number.
| Model | Serial ranges |
|---|---|
| C11 | Serial range not listed in source records |
| C13 | Serial range not listed in source records |
| C175 | Serial range not listed in source records |
| C27 | Serial range not listed in source records |
| C32 | Serial range not listed in source records |
Frequently asked questions
What does CAT fault code 178510 mean?
It means the ECM detected that the intake manifold pressure sensor signal was not fluctuating normally, staying abnormally steady for more than 30 seconds while the engine ran above 1000 rpm. This is logged as SPN 102 / FMI 10.
Will code 178510 cause a derate or shut down my engine?
It does not shut the engine down, but it can cause noticeably poor acceleration because the ECM defaults the wastegate solenoid signal (on engines with an electronically controlled wastegate) to protect against turbocharger overspeed and intake overpressure.
Can a bad connector cause this code?
Yes. Damaged, corroded, or loose connectors and wiring are listed as a primary possible cause, along with intermittent harness faults from abrasion or pinch points.
Is the intake manifold pressure sensor damaged, or is it a wiring issue?
It could be either. Start with the wiring and connectors since those are the most common and cheapest fix. If the supply and signal circuits both test good, the sensor itself, or in rarer cases the ECM, may be at fault.
Does this code affect other sensors too?
It can. The intake manifold pressure sensor shares the ECM's regulated 5.0 ± 0.2 VDC supply circuit with several other sensors, including the atmospheric pressure sensor, crankcase pressure sensor, and engine oil pressure sensor. A supply-side fault may trigger multiple related codes at once.
What engines does code 178510 apply to?
This code applies to CAT C11, C13, C175, C27, and C32 engines.
Is there a special reset procedure after repairing the fault?
No reset procedure is listed for this code. Repairing the wiring, connector, or sensor issue and confirming normal signal fluctuation above 1000 rpm should allow the code to clear on its own during normal operation.