How do you adjust idle for Toyota paseo?

Answer 1

You have to bypass the idle air control valve to baseline your Paseo's idle -- you can't just twirl the screw on the manifold -- the computer will try to compensate and your fueling will be thrown off, possibly causing driveability problems, definitely impacting your fuel economy.

You'll need: an inductive tachometer that clips onto the high tension plug lead, a paper clip jumper, and a blade screwdriver.

First, engage your parking brake, chock your rear wheels (preferably with a 4-by-4 pice of wood or store-bought chocks)and make sure your work area is well-ventilated.

Now, the following is the procedure in the factory service manual (of which I use to service my own '92). This assumes that you have no vacuum problems, you're using the stock air filter and ducting, transmission is in neutral, engine is warm, and no accessories are on.

1. Attach the tachometer to the high tension leads to #1 plug, to determine true engine rpm. You shouldn't use the stock tach; it can be inaccurate for this adjustment.

2. Start engine and rev to 2500 rpm for two minutes (this is to warm the engine so cold fast idle isn't enabled, but not warm enough to kick the cooling fan on).

3. Pop the hood with the car idling, and find your diagnostic port, to the side of your fuse box, behind the battery. There'll be a diagram inside the lid. Find the E1 and TE1 ports. You're going to jump these with a paper clip, to disable the idle air control. DO NOT JUMP ANY OTHER PORT.

4. Insert the ends of the paper clip jumper (Toyota has a special tool, but it's just a fancier jumper) into ports E1 and TE1. You should hear a change in the engine sound, a distinct ticking. This is normal.

5. Get a small blade screwdriver and remove the black plug protecting the idle adjustment screw at the top of the aluminum intake manifold. Adjust your idle using the tachometer until it sits at 750 rpm exactly. If your cooling fan kicks on, you'll have to wait until it shuts off before doing your adjustment.

6. When your tach shows a steady 750 rpm, pull out your paper clip jumper. Your idle will change slightly as the computer attempts to adjust. Replace idle screw plug, close diagnostic port cover.

7. Give your Paseo a few days to adjust to the change. On mine, the idle was set too low by a dealer, and when corrected, gave me ~2 - 3 mpg improvement, as well as much better response and power. However, your computer 'writes' corrections it learns about your driving style only when the key is turned off, then applies what it's learned when the car is started again. So give it a few cycles with some typical driving (for you), and you should see easily 30 - 34 mpg (my 208K Paseo still gets 32 - 36 mpg, depending on how much freeway time it gets per tank).

Good luck...