Hi

My volvo is having symptoms of a dirty throttle body. I've cleaned the TB a couple of times in the past. So removing and putting it back in is not a problem. What I'm umsure about is THE correct procedure for setting the idle on a k-jet as mine which is an 89 B230E with a Bosch mechanical injection aka k-jet. There's scant information on this model in the FAQ and in chilton or haynes. Mine is a non-CIS. It has no o2 sensor, no cat. It has an auxillary air valve and a microswitch (small white box with a spring)

Below is what I intend to do. It is based from the chilton, haynes and from what I've gathered over the years from the brickboard. Please feel free to comment or give suggestions

1. After cleaning the throttle body slacken the microswitch allen screws. Install throttle body.

2. Start engine. When engine is warm, make sure AAV is closed and close the black bypass knob.

Question : How do one close the AAV on a running engine? Won't step 2 cause the engine to stall?

3. Adjust throttle stop screw. Method A) Adjust throttle stop screw so engine barely runs, maybe 600-650 rpm. Method B) Screw in the throttle stop screw until it just contacts the lever. Then tighten the screw a further 90 to 180 degrees (1/4 to 1/2 turn) and tighten the locknut

Question : Any preference which is better?

4. Set "Curb Idle Speed" by adjusting the black bypass knob for final setting of the idle speed

5. Turn off engine

6. Tighten the microswitch screws so that the switch clicks the moment the throttle starts to open. To adjust the throttle micro-switch, insert 0.12 in. (3mm) feeler gauge between the throttle position adjustment screw and the throttle stop

Question : This was taken from chilton. It was referring to K-jets without a CIS system (B28F). Not sure if a feeler gauge is necessary or even relevant to mine

7. Check automatic transmission kickdown cable length first on automatic trans models. Adjust as below
Method A (Haynes-not specified to which model) A small gap (0.25 to 1 mm) should be present between crimped stop and the adjuster sleeve in idle position. Open throttle measurement should be checked with the throttle pedal in the car depressed. With open throttle, it should be 1.97 in. (50mm)
Method B - as per FAQ

Question : Do you guys actually take out a feeler gauge and a vernier caliper and do the measurements? I've been doing it the A method in the past.

8. Reconnect the throttle control rod at the cable pulley. Place 1 mm feeler blade between cable drum and idle stop. In this position the the clearance between throttle lever and and adjustment screw must be 0.1mm. Adjust the control rod to achieve this.

Question : Again same question, really necessary?

9. Take the car for a spin and enjoy! (hopefully)

Sorry if this is a long post. At the moment I find myself needing to clean the TB every six month. Hence the need to get my steps correct. I'm not sure if a 6 monthly TB cleaning is normal with a k-jet (it being unable to compensate for it's idle). Appreciate your thoughts. Thanks

Aslan
Malaysia