How To:- Manual Choke Conversion Instructions
The Woodsport Manual Choke conversion for a MK1
The average mk1 owner should have no problem at doing this conversion but the following instructions should make it straightforward if a little patronising to more experienced owners.
1. Suitable 12v air solenoid. Best one to use is the aircon idle up VSV ( Vacuum Solenoid Valve ) from a MR2MK2 part number is 90910-13003 this valve is adjustable and allows you to set the cold idle speed to your preference. But almost any air solenoid with 6/8 mm ports will work. The smaller the ports, the lower the idle will be. Too small and it won't idle when cold.
2. Suitable switch if you get the correct size you can utilise the blank next to the coin holder on the dash
3. 8 mm ID vacuum tubing
4. Enough suitable wire to run from the dash to the chosen location of the solenoid. Or you can utilise the unused cruise control wiring that runs from the steering column area to the rear boot. See this article for details. CLICKY
5. A suitable plastic tyre valve cap
6. A selection of hands tools.
Ensure the engine is cold before starting to fit.
1. Undo the clip on top of the throttle body and remove the rubber intake air filter pipe.
2. Looking into the throttle body there’s a 5p sized hole at 5 o’clock C in the picture, insert the plastic valve cap into the hole and press it in as hard as you can.
3. Re-attach the air intake pipe and secure the clip.
4. Find a suitable location for your solenoid and mount it, if you want to keep it dry, there is plenty of room on the LHS behind the trim panel in the boot.
5. Pictured above (pipe B) is the throttle bypass pipe we are going to use to attach the manual choke valve to. Remove the rubber end cap from it with pliers.
6. Run a piece of 8 mm ID tubing from B to the solenoid valve.
Note. If your using the MK2 aircon VSV it must go to the port WITHOUT the adjuster (bottom port).
7. Pipe A in the picture is a spare fitting found on most mk1s, remove the rubber end cap from it and run a piece of 8 mm ID tubing from it to the other port (top port) on the solenoid. If your mk1 hasn’t got this fitting or has an aftermarket air filter you can put a small filter straight onto the other solenoid port. ( these are available cheaply on eBay )
If you decide to use the spare cruise control wiring you can ignore part 8.
8. Route a wire from the solenoid through the bulkhead and behind the passenger side bulkhead trim. There are several routes to choose from to route this wire to the dash, it doesn’t matter which route you choose as long as the wire exits from the switch blank.
9. Run a 12v supply to the same location. A good place to get this is from the stereo supply, if you remove the stereo ( easy to do ) you can reach up behind the dash from the pedal area and feed the wire through to the stereo, you can then connect up the switch and push it into place without having to remove the lower section of the dashboard ( loads of screws )
10. At the solenoid connect up the wire you have just run ( or the wire you have chosen from the Cruise wiring ) to one terminal of the solenoid, run a wire from the other terminal to a good chassis earth.
11. Start the engine using a quick blip of the throttle then let it idle, revs should be at around 1300rpm and will rise steadily to 2000 rpm after 20 seconds or so.
If your using the MK2 aircon VSV you can adjust the 2000 rpm down to a figure that suits you, by using a 4 mm allen key on the adjuster on the top port of the VSV
12. If the engine will not idle then the valve isn’t getting a power supply (check all your connections and the earth).
13. Switch the choke off after 60 seconds or so (the engine should idle by itself, if not then switch the choke back on for a further period until it does). You will note that you can switch the choke off far earlier than the Toyota waxstat ever did.
14. Get the engine up to full running temperature and adjust the base idle speed to 900-1000rpm using screw D located on top of the throttle body.( With the solenoid OFF)
Enjoy !! Compliments of
Copyright © by MR2 Owners Club All Right Reserved.