Throttle position sensor (TPDZ) on Nissan Sunny with engine QG15DE - a critical element of the injection system, the accuracy of which determines the stability of idle speed, responsiveness of the gas pedal and fuel consumption. Over time, the sensor contacts wear out, and the factory settings are lost due to vibrations or unqualified repairs. In 80% of cases, “floating” speeds or jerks during acceleration are eliminated by adjusting the TPS, and not by replacing it.

This article is not a theoretical review, but practical guide with photographs of key stages, multimeter connection diagrams and resistance tables for QG15DE. We will look at how to diagnose a malfunction without a scanner, adjust the sensor manually and check the result. We will pay special attention A typical mistake during adjustment is ignoring the position of the throttle stop screw, due to which the adjustment is lost after 100–200 km..

Signs of a TPS malfunction on a Nissan Sunny QG15

Symptoms of a bad throttle position sensor are often confused with problems Mass air flow sensor, RXX or even ignition coils. In order not to waste time on diagnostics “blindly”, pay attention to specific manifestations:

  • 🔴 Floating speed at idle (from 600 to 1200 rpm) after the engine has warmed up.
  • 🚗 Jerks during acceleration at speeds of 40–60 km/h, especially when gently pressing the gas.
  • ⚡ Check Engine light comes on with errors P0120 (TPS circuit malfunction) or P0122 (low signal level).
  • 🛑 RPM freezing after releasing the gas (for example, when braking the engine).
  • 💨 Increased fuel consumption (1–2 liters more than usual) for no apparent reason.

On Nissan Sunny with motor QG15DE The TPS is installed on the throttle body and connected to the ECU with a three-wire connector. Structurally this potentiometer, which converts the mechanical position of the damper into an electrical signal. If the sensor fails, the ECU goes into emergency mode using averaged data - hence the unstable operation of the engine.

⚠️ Attention: On QG15DE after 2003, TPS may be contactless type (based on the Hall effect). Such sensors are not adjustable - only replacement! Check the markings: if there is an inscription on the body HALL EFFECT, adjustment is useless.

Tools and preparation for adjustment

To configure the TPS yourself, you will need:

  • 🔧 Multimeter (preferably digital with an accuracy of 0.1 V).
  • 🔩 Phillips head screwdriver (for dismantling the throttle assembly).
  • 🧲 Thin flathead screwdriver (to adjust the thrust screw).
  • 🧴 Carburetor Cleaner (For example, Abro or LIQUI MOLY).
  • 📝 Marker or proofreader (for marking).

Before starting work, complete the required steps:

Disconnect the negative battery terminal for 10 minutes (ECU reset)

Remove the air duct from the throttle assembly

Clean the damper and idle air passage from carbon deposits

Check the free movement of the damper (there should be no jamming) -->

If the throttle valve is dirty, adjusting the TPS will not work - the ECU will receive incorrect position data. Use soft cloth and a purifier, but not metal brushesso as not to damage the coating.

Abro Carb Cleaner

LIQUI MOLY Pro-Line

Hi-Gear

Other brand

I don't clean it ->

Multimeter connection diagram and signal checking

TPS on Nissan Sunny QG15 has three contacts:

Wire color Purpose Normal voltage
Red (+5V) Powered by ECU 4.8–5.2 V
Black (GND) Weight 0 V
Green/Blue Signal (to ECU) 0.3–4.7 V (depending on the damper position)

To check:

  1. Connect negative probe multimeter to mass (black wire).
  2. Turn on the ignition (without starting the engine).
  3. Measure the voltage at red wire - must be ~5 V.
  4. Connect positive probe to signal wire (green/blue).
  5. When closed damper the voltage should be 0.3–0.7 V, at completely open — 4.0–4.7 V.

If the voltage on the signal wire goes beyond or changes abruptly when the damper opens smoothly, the sensor is faulty. Also check resistance between the signal and ground contacts: when the damper is closed, it should be 1.5–2.5 kOhm, when open - 4.5–6.5 kOhm.

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If you don’t have a multimeter, you can check the TPS “by eye”: when you smoothly open the damper manually, there should be no jamming or jumping. But this method is not accurate - it is better to borrow a device or buy an inexpensive one (from 300 rubles).

Step-by-step adjustment of TPS without dismantling the throttle

If the check shows that the sensor is working, but the signal is not normal, adjustment is required. On Nissan Sunny QG15 it's being done without removing the throttle body:

  1. Loosen the two TPS mounting screws (do not unscrew completely!).
  2. Install the damper in fully closed position (you can press your hand all the way).
  3. Connect the multimeter to signal wire (as described above).
  4. Rotate the TPS body clockwise, if the voltage above 0.5 V, or against - if lower.
  5. Achieve value 0.45–0.55 V and secure the screws.

After adjustment, check maximum damper opening: The voltage should gradually increase to 4.0–4.7 V no jumps. If this does not happen, the sensor is worn out and requires replacement.

What to do if the voltage “floats” even after adjustment?

This is a sign of wear of the resistive layer inside the TPS. A temporary solution is to clean the contacts with alcohol, but this will not help for long. The best option is to replace the sensor (part number for QG15DE: 22680-4M000 or analogues Hella, Bosch).

⚠️ Attention: Do not use sealant or glue to fix the TPS after adjustment! This will lead to corrosion of the contacts. The screws must be tightened firmly 0.5–0.7 Nm (do not overtighten!).

Adjusting the Throttle Throttle Screw

Many car owners forget that Nissan Sunny QG15 damper closed position Adjustable with a separate screw. If you don’t set it up, the TPS adjustment gets lost after a few hundred kilometers. Procedure:

  1. Remove the plastic plug from the thrust screw (it is located next to the throttle cable).
  2. Check the gap between the damper and the body - it should be 0.1–0.3 mm (you can use a feeler gauge).
  3. If the gap is larger, tighten the screw clockwise, if less, loosen.
  4. After setup necessarily repeat the TPS adjustment (see previous section).

On some versions QG15DE The thrust screw is covered with paint - this is a factory mark. Don't remove it unless necessary! If the screw has never been adjusted, the clearance is likely normal.

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Adjusting the thrust screw and TPS is two separate procedures, but they must be performed sequentially. If you adjust only the sensor, ignoring the mechanical stop, the problem will return in 1-2 weeks.

Checking the result and adapting the ECU

After adjustment you must:

  1. Connect the battery and start the engine.
  2. Warm up the engine to operating temperature (80–90°C).
  3. Check the idle speed - it should be 650–750 rpm.
  4. Press the gas sharply 2-3 times and release - the speed should smoothly return to normal.

If the speed “floats” or is too high, perform ECU adaptation:

  1. Reset the battery terminal for 10 minutes.
  2. Plug it back in and don't start the engine.
  3. Turn the ignition on for 5 seconds, then turn it off (repeat 3 times).
  4. Start the engine and let it idle for 5 minutes.

This procedure resets the adaptive settings of the ECU, and it “remembers” the new TPS parameters. If the problem persists, check RXX (idle air control) or air leak in the intake manifold.

Common mistakes and how to avoid them

Even experienced craftsmen make mistakes when adjusting the TPS on Nissan Sunny QG15. Here are the most common:

  • 🔧 Ignoring the Thrust Screw — leads to repeated failure after 100–200 km.
  • ⚡ Adjustment with ignition on - can burn the ECU (always remove the terminal!).
  • 📉 Using a faulty multimeter — check the device on a different power source.
  • 🛑 Tightening the TPS screws with force — deforms the body and throws off the settings.
  • 💨 Adjustment on a cold engine — the parameters will change after warming up.

Another typical problem is dirt ingress between the damper and the housing after cleaning. Always bleed the throttle body compressed air after using the cleaner.

⚠️ Attention: On Nissan Sunny with automatic transmission after adjusting the TPS, it may be necessary automatic transmission adaptation reset. To do this, disconnect the connector on the box (located next to the engine ECU) for 10 seconds.

FAQ: Frequently asked questions about TPS adjustment

Is it possible to adjust TPS without a multimeter?

Theoretically yes, but this is an imprecise method. You can focus on the smoothness of the damper movement and the absence of jerks during acceleration, but without checking the voltage it is impossible to guarantee the correct setting. If you don’t have a multimeter, it’s better to contact a service center.

How often do I need to adjust the TPS on the QG15DE?

Under normal operating conditions, adjustment is required once every 50–80 thousand km or after repairing the throttle assembly. If the vehicle is driven in high humidity or dusty conditions, check the sensor every 30 thousand km.

What is the difference between TPS on a Sunny with a carburetor and an injector?

On carburetor versions Nissan Sunny (until 1995) TPS was not installed - instead it was used limit switch (micro switch) for forced idle economizer. On injection QG15DE analog sensor, with smooth signal transmission.

Can I use TPS from another Nissan?

Yes, but only if the sensor has similar technical parameters. For example, a TPS from Nissan Almera N16 (article 22680-4M010) or Primera P12. Before installation, be sure to compare the resistance and voltage with the original sensor.

Why is the speed high after replacing the TPS?

This is a normal phenomenon - the ECU has not yet adapted to the new sensor. Perform the reset procedure (see section “Checking the result”), and the speed will return to normal after 5–10 minutes of engine operation.