Description
Aftermarket replacement injection actuation pressure (ICP) sensor for Caterpillar HEUI-injected engines — 3126, 3126B, 3126E, C7, C9, and the 3056E / 3524B industrial variants. Replaces Cat 224-4536 and the earlier 141-4122, 167-1708, and 194-6726 numbers it superseded. 3-pin Cat triangular Deutsch-style connector, 1/2″-20 thread, 16.75 in pigtail. The sensor monitors high-pressure oil at the HEUI rail; failure causes hard starts, intermittent stalls, and cylinder-cut codes.
Signs You Need a New Injection Actuation Pressure Sensor
- Hard start or no start when the engine is hot
- Active fault codes for ICP / injection actuation pressure (CID 164, etc.)
- Low power, derate, or cylinder cut-out under load
- Engine stumbles or stalls at idle
- Rough running with no obvious mechanical cause
Specifications
| Manufacturer | Aftermarket (PAI-style replacement) |
|---|---|
| Part Number | 224-4536 (Cat OEM equivalent) |
| Part Type | Injection Actuation Pressure Sensor (ICP) |
| Pin Count | 3 |
| Connector | Triangular (Cat HEUI pattern) |
| Thread Size | 1/2″-20 |
| Overall Length | 16.75 in (with pigtail) |
| Color / Finish | Black / Brass |
Cross References
This sensor replaces or is equivalent to the following part numbers:
- Caterpillar: 224-4536, 2244536, 194-6726, 1946726, 167-1708, 1671708, 141-4122, 1414122
- Also known as: 3PP6-1, 236-6220
Applications
This injection actuation pressure sensor fits the following Caterpillar HEUI engines:
- Caterpillar 3126, 3126B, 3126E (1998–2003 on-highway and industrial)
- Caterpillar C7 (on-highway, 2004+ — ACERT and pre-ACERT)
- Caterpillar C9 (on-highway and industrial)
- Caterpillar 3056E industrial
- Caterpillar 3524B off-highway truck
Representative trucks and equipment using these engines:
- Freightliner Business Class M2 with 3126 / C7
- International / Sterling medium-duty with C7
- School and transit buses with 3126 / C7
- Caterpillar wheel loaders 928G, 966D, 966E, 966F
- Caterpillar telehandlers TH series with 3056E
Replace the sealing washer at the sensor port and check for clean engine oil before installing — a contaminated HEUI rail will damage a new ICP sensor quickly.
