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17113209 TPS & IAC Set for LS Chevy GMC: Fitment, Specs, DTC Coverage

The Throttle Position Sensor & Idle Air Control Valve Set (PN: 17113209) is built for GM LS-series cable-driven throttle bodies across the 4.8L, 5.3L, and 6.0L Vortec/LS platform. It targets the known failure modes of the 1996-2007 GM light-truck and SUV range and replaces OEM numbers 17113209, 3843751, 803149, 8171132090, 17076283, and AC147.

• Chevrolet Silverado 1500/2500, Tahoe, Suburban, Express, S10, Astro
• GMC Sierra 1500/2500, Yukon, Sonoma, Savana, Safari
• Isuzu NPR and W-Series

It fits cable-driven LS1, LS2, LS6, LSX, and LS7 throttle bodies. It is not intended for electronic-throttle (ETC/DBW) applications, so check for a throttle cable before you order.

2026 Compliance in Plain Terms

Manufacturing follows IATF 16949:2026 quality protocols. Diagnostics comply with SAE J1979-2 OBDonUDS, including the 3-byte expanded DTC naming convention effective MY2026. The analog output interfaces with CAN 2.0B and CAN 3.0 ECUs through the stock 3-pin sealed Metri-Pack connector, so the part pairs with legacy ECUs and 2026 CAN-bus 3.0 scan tools.

The sensor element is a sealed conductive-film potentiometer rated for 100,000+ operational cycles at −40°C to +125°C, exceeding SAE J1349 environmental durability benchmarks.

Spec Comparison

Data from Koeep internal validation reports, GM service documentation (Document ID 2173849), and SAE J1349/J1979-2:2026 reference standards. Figures are nominal; real-world results vary with installation conditions and ECU calibration.

Materials and Signal Integrity

Throttle position sensor

The housing is glass-fiber-reinforced PPS, the composite class Bosch validated in 2025-2026 throttle body programs for thermal stability up to 220°C intermittent exposure. Laser-trimmed precious-metal alloy wiper contacts on a ceramic substrate hold linearity deviation at ≤0.5% across the full 84° rotational sweep.

Idle air control valve

A high-torque stepper motor with PTFE-impregnated bearing surfaces runs 255 discrete step positions with ±1 step repeatability over 500,000 actuation cycles. The dual-solenoid design eliminates the mid-life hysteresis drift that single-wound IAC units develop after about 60,000 miles of mixed-duty cycling.

DTC Mapping

This set addresses three code families: TPS circuit faults, idle control faults, and the cross-linked codes they trigger.

TPS circuit faults

• P0120 Circuit Malfunction
• P0121 Range/Performance
• P0122 Low Input / Short to Ground
• P0123 High Input / Short to VREF
• P0124 Intermittent

In the OBDonUDS 3-byte format (MY2026+) these log as P0120-11 through P0124-2F.

Idle control faults

• P0505 Idle Control System
• P0506 RPM Lower Than Expected
• P0507 RPM Higher Than Expected

Cross-linked codes

P0400 (EGR flow) can set when an IAC malfunction alters the intake vacuum profile. P0171 and P0174 (lean bank 1 and lean bank 2) can set when idle instability corrupts fuel trim learning. Replacing the failed part removes the trigger for both.

Symptoms and Root Causes

P0120: idle surging to 1,200-1,800 RPM

P0120 means the ECU sees erratic or out-of-range voltage on the TPS signal circuit (Pin B, signal return). A 2026 OBDonUDS scan tool may log it as P0120-11, circuit short to ground.

The common LS failure is carbon-track wear at the closed-throttle rest position, roughly 0° to 5° of rotation. Voltage spikes from 0.45V past 0.85V, the ECU reads that as a throttle-open command, and an idle-air compensation loop drives RPM to 1,200-1,800. Replacing the 17113209 TPS/IAC set fixes the root cause instead of masking it with ECU reflashes.

P0505, P0506, P0507: stalling at stoplights after a cold start

These three codes point to IAC stepper degradation. On these throttle bodies the pintle collects carbon from PCV oil vapor and binds at step positions 0 to 40, the cold-start high-idle range. Mode $06 under the 2026 OBDonUDS standard logs IAC step-count deltas, so you can catch mid-range sticking before limp mode.

The Koeep IAC uses PTFE-impregnated pintle guides that resist carbon adhesion; tested MTBF exceeds 120,000 miles.

P0121: check the hardware first

P0121 sets when the ECU compares TPS voltage against MAF and MAP correlations and finds a rationality error: the throttle angle the voltage reports does not match airflow and manifold pressure. The sensor is not always the guilty part.

First verify the throttle blade stop screw has not been tampered with (common on used LS intakes) and that the throttle cable returns fully to the mechanical stop. If the body passes that check, replace the TPS and IAC as a matched set. A new TPS with a worn, leaking IAC still trips P0121 under 2026-enhanced ECU monitoring.

Idle Relearn Procedure (2026 Scan Tools)

An idle relearn is required after installation. The steps:

1. Clear all DTCs using Mode $04.
2. Key ON, engine OFF for 30 seconds so the ECU registers the new closed-throttle reference voltage.
3. Start the engine and reach full operating temperature (ECT above 85°C).
4. Apply all electrical loads (high beams, HVAC blower max, rear defrost) for 60 seconds to trigger the IAC learned-position routine.
5. Return to idle with no loads for 30 seconds.

Long-term idle trim (Mode $06 TID $0C) should stabilize within ±2 IAC steps. With a 2026 J2534-2 pass-through device, OBDonUDS service $31 routine RID $E010 automates the procedure.

Installation Checklist

1. Confirm the throttle body is cable-driven, not ETC/DBW.
2. Check the 3-pin Metri-Pack connector for terminal fretting corrosion; apply Stabilant 22A contact enhancer.
3. Torque the TPS mounting screws to 2.0 N·m (18 in-lbs). Over-torque cracks the PPS housing.
4. Run Mode $01 PID $11 validation: closed throttle 0%, wide open 100% ±2%.
5. Complete the idle relearn above.

Build Standard and Lifecycle

The TPS housing is PPS GF30 with a UL94 V-0 flame rating; the IAC stepper housing is PBT GF20 with a PTFE-impregnated pintle bushing. The facility is certified to IATF 16949:2026 (superseding ISO/TS 16949). Every sensor element gets 100% end-of-line laser calibration traceable to NIST voltage standards, and the PCB carries conformal coating per IPC-CC-830B for moisture and hydrocarbon resistance.

Reference standards: SAE J1349, SAE J1930 terminology, IATF 16949:2026 Clause 8.5.1. Koeep PN 17113209 is an Active Lifecycle product with projected service availability through 2030 minimum. An estimated 12.8 million cable-driven LS/Vortec engines were still in service across North America as of Q1 2026.

Cross-reference is validated against GM EPC v2026.1 for RPO codes LM7, LR4, LQ4, LQ9, LS1, LS6, L59, LM4, and L33.

2026 market context

Ford, GM, Toyota, and Tesla have moved new production to electronic throttle control, a segment projected to reach $29.12 billion in 2026. Cable-driven throttle bodies still matter for fleet maintenance, restoration, and tuning: the Toyota 2TR-FE and Nissan VQ40DE keep cable designs in select 2026 global-market variants, while Tesla runs no IAC and no cable at all.

Related Parts and Guides

Working across a mixed GM fleet? The Throttle Position Sensor & Idle Air Control Valve for Chevy GMC Cadillac Buick covers the same repair on additional GM applications, and the Throttle Sensor+TPS Position Idle Air Control Valve for Chevy GMC Buick Cadillac is the alternate listing. For the wider catalog, browse Air & Fuel Delivery Parts.

Chasing steering wander on an older truck too? The guide to the Complete Suspension Front Ball Joint Pitman Idler Arm Kit for Chevy & GMC C2500 C3500 covers the steering-control rebuild.

Frequently Asked Questions