Parts for your 1999 Nissan Navara-Throttle position sensors

1999 Nissan Navara throttle position sensor (TPS) — what it does and when to service it

Referencing the Nissan D22 Factory Service Manual (EC section) and aftermarket workshop guides for the D22 platform (1997–2004), a throttle position sensor is fitted to 1999 Navara petrol models with the KA24E EFI engine. Those sources show the TPS mounted on the throttle body, providing a variable voltage signal to the engine control unit. For 1999 diesel D22s (TD27/QD32 mechanical-injection engines common in AU/NZ), there is no conventional intake throttle plate and therefore no traditional TPS. Some diesels may carry a simple switch or an accelerator position sensor on the injection pump for EGR/timing control, but it’s not the same part or role as a petrol TPS.

For petrol 1999 Navara owners, the TPS is a small, adjustable sensor on the throttle shaft that tells the ECU exactly how far the throttle is open. That lets the ECU fine‑tune fuel, ignition timing, and gearshift behaviour in autos. When it’s healthy, throttle response feels crisp, idle is steady, and fuel economy stays on target. When it goes out of spec you’ll often see erratic idle, flat spots on take‑off, surging at steady cruise, or the check‑engine light with codes like P0120–P0123.

Servicing the TPS is straightforward. On the KA24E, technicians typically check the closed‑throttle voltage (around 0.45–0.55 V with key on, engine off) and confirm a smooth rise to roughly 4 V at wide open throttle. The sensor sits in slotted holes so it can be rotated slightly to set base voltage and ensure the “closed throttle” switch state is correct. After adjustment or replacement, clear any fault codes and perform the idle learn procedure as outlined in the D22 service manual so the ECU settles into a stable idle.

Replacement is sensible if the voltage sweep has dead spots or jumps, or the idle switch state won’t set within spec. Use a quality sensor, avoid twisting the throttle shaft while fitting, and don’t drown the area in cleaner—solvent can wick into the sensor. A quick look under the bonnet during routine servicing to check the connector fit, wiring condition, and that tell‑tale smooth voltage sweep can save chasing drivability gremlins later. For diesel 1999 Navaras with mechanical pumps, a TPS isn’t part of the system, so any throttle‑related concerns are usually down to cable/linkage adjustment, pump tuning, or EGR controls rather than a TPS fault.

• Common TPS symptoms on petrol KA24E: uneven idle, hesitation, harsh auto shifts, higher fuel use, and TPS‑related fault codes.
• Basic care: keep the connector clean and tight, verify smooth voltage sweep during services, and recalibrate after replacement.

Popular questions

Does a 1999 Nissan Navara have a throttle position sensor?
Petrol KA24E models do—it's on the throttle body and talks to the ECU. Mechanical‑injection diesels (TD27/QD32) don’t use a conventional TPS because there’s no intake throttle plate, they may have pump‑mounted switches or an accelerator position device for emissions control, which is a different setup.

What are the signs the TPS is failing on a 1999 Navara petrol?
Look for a shaky idle, flat spots on acceleration, surging at steady speed, harsher auto shifts, and a check‑engine light. On scan, you may see P0120–P0123 or a throttle angle that jumps instead of sweeping smoothly as you open the throttle.

Does the TPS need calibration after replacement?
Yes. With key on, engine off, set the closed‑throttle voltage to roughly 0.45–0.55 V by rotating the TPS in its slotted holes, confirm a smooth rise to about 4 V at full throttle, tighten the screws, clear codes, and carry out the idle learn procedure from the D22 manual.