Autopapyrus · Daihatsu Thor 1.0 (2018)
https://autopapyrus.com/guides/daihatsu/thor/throttle-body-cleaning/
https://autopapyrus.com/guides/daihatsu/thor/throttle-body-cleaning/
Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.
Daihatsu Thor 1.0 (2018): Throttle Body Cleaning
The Daihatsu Thor is the Toyota Roomy/Tank version with the 1.0 L (69 hp) engine, and its throttle body is electronic. Carbon buildup causes an unstable idle and hanging revs. Clean it carefully: do not turn the throttle plate by hand and do not flood the electronics. After cleaning, the engine control unit must relearn the throttle position.
Key figures
- Inspection interval with gentle drivingwhen to first look under the duct and check the throttle plate (step 4)about 100 thousand km
- Interval with aggressive drivingafter this mileage, carbon buildup may already affect engine operation (step 4)40-50 thousand km
- Waiting time for the relearnthis is how the control unit memorizes the closed throttle position (step 13)30-40 seconds with the ignition on, then 15 seconds with it off
Check these values against the manufacturer’s specification for your vehicle before you start.
Diagram: where the throttle body is and how to remove the duct for cleaning
Tap to enlarge
- 1Throttle body: sits between the duct and the intake manifold and has an electrical connector. This is what you clean.
- 2Throttle plate with dark carbon: wipe it and its edge with a cloth and cleaner. Do not turn or press it by hand.
- 3Corrugated duct from the air filter: after loosening the clamp, pull it off the throttle body; disconnect the crankcase vent hoses if needed.
- 4Duct clamp: loosen it to remove the duct and tighten it on reassembly.
- 5Drive unit with connector: electronics, keep cleaner away from the connector and the drive motor.
- 6Mounting bolts or nuts (2-4): only needed if you remove the whole unit; tighten evenly.
- 7Intake manifold: when the unit is off, cover its opening with a clean cloth to keep dirt out.
Parts
3| № | Part |
|---|---|
| 01 | Throttle body cleaner (aerosol) |
| 02 | Gasket or seal ring between throttle body and intake manifoldif damaged |
| 03 | Throttle body duct clampsif damaged |
Tools
6- Socket and wrench set (usually 10 mm and 12 mm)
- screwdrivers
- soft brush
- clean lint-free wipes
- throttle body cleaner (aerosol)
- compressed air (optional)
Step by step
15 steps- Shut off the engine and let it cool down. Open the hood and locate the throttle body. It sits on the intake manifold between the corrugated duct from the air filter and the manifold, and it has an electrical connector.
- Disconnect the negative battery terminal and wait a few minutes to de-energize the electronics.
- Loosen the clamp and remove the air duct from the throttle body. If necessary, disconnect the crankcase ventilation hoses from it. Remember which hose was connected where.
- Inspect the throttle plate. The carbon buildup comes from dust and oil mist from the crankcase ventilation system. The more worn the engine, the faster it builds up.
- The simplest and safest method is cleaning in place. Do not press on the throttle plate with your finger and do not force it to turn: the drive is electric, the gears are easily damaged, and the control unit has to relearn the plate position.
- If you need to open the plate slightly, turn the ignition on for a few seconds and do not touch the accelerator pedal. For cleaning, it is best not to move anything by hand and to work on the accessible edges.
- Apply the cleaner to a wipe or a brush, rather than spraying it onto the throttle plate. Wipe the plate, its edge and the inside of the housing until the dark deposit is gone. Do not let liquid get onto the connector or into the drive motor. Do not flood the electronic throttle body with cleaner: it can be ruined.
- Do not soak rubber parts in solvent or gasoline: the seal ring and gaskets will deteriorate.
- If you remove the throttle body completely (2-4 bolts or nuts), cover the intake manifold opening with a clean wipe so dust and dirt do not get inside. Tighten the fasteners evenly to the manufacturer's specified torque (for small bolts on this type of unit, usually about 8-20 N·m (6-15 lb-ft)). Inspect the seal and replace it if it is dry or torn.
- Let the parts air dry or blow them off with compressed air. Remove the wipe from the manifold before reassembly.
- Install the air duct, tighten the clamp, reconnect the crankcase ventilation hoses, and check that the sensor connector is seated firmly.
- Reconnect the negative battery terminal.
- Relearn procedure: turn the ignition on for 30-40 seconds without pressing anything, so the control unit can record the closed throttle position (you may hear a light whirring). Then turn the ignition off, wait about 15 seconds, and start the engine.
- Let the engine idle and warm up. At first the revs may fluctuate slightly or rise a little. If so, shut off the engine and start it again. Usually everything returns to normal after a few starts.
- If the idle remains rough, the Check Engine light comes on after cleaning, or the engine stalls, the throttle will need to be relearned with a diagnostic scan tool. In that case, take the car to a repair shop: the cause may not be the throttle body (spark plugs, ignition coils, air leak).
Common mistakes and warnings
- Never turn an electronic throttle body by hand or flood it with cleaner
- If you are not confident in your skills, leave the job to a repair shop, and when choosing one, make sure they actually clean the throttle body rather than just wiping the surface: otherwise the dirt ends up in the intake manifold
- With aggressive driving, carbon buildup can appear after as little as 40-50 thousand km; with gentle driving, plan an inspection at around 100 thousand km