240 idles slowly and sometimes needs some gas pedal pressure to keep going when first starting. Recently has begun to stall out when stopped.
I cleaned throttle body last year, and tuned up ignition system.
What else should I check?
Frank

i have a 91 240 and did some minor adjustments to correct a minor idle problem. First i read all the archived posts and the haynes manual. the posts are better than the manual. My 91 does not have an idle control switch, it has an idle control RHEOSTAT which sends a nonlinear signal to the ignition control module. I cleaned the throttle plate and checked my vacuum lines. I made noticeable progress when i removed and cleaned out the idle control valve. it can get dirty and will subsequently stick, restricting air flow during idling conditions (when you are not pressing on the accelerator).

After doing those simple things, i connected a digital tach and adjusted the idle to 750rpm +/-50rpm with the control linkage located below the throttle. Do not attempt to adjust the screw that is factory set; imho, it can screw you up more than anything else.

good luck

btw, i luv this board, but i have discovered sometimes the well-meaning information here is great for the older 240s, but things changed in 90, 91, etc so you gotta carefully pick and choose from what you read.

It's likely a vacuum leak somewhere on the intake hose or the throttle body, or a bad idle air switch. If the idle air switch on the throttle body is stuck open, you won't get the proper airflow through the throttle body for steady idle. There are procedures in most aftermarket manuals, and I think in the 700/900 FAQ about setting the switch and verifying that it's working right.

It might pay to check the codes stored in the computer's diagnostic memory. Also described in above sources.
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chris herbst, five volvos.

My 1980 GT had the same problem the engine set up changed a little bit but for me it was a Constant pressure regulator. 150 dollar part (usually about 5 at any junk yard) And a air slide 125 dollars (about 2.50 at any junk yard) I dont know the exact engine set up of your car I am pretty sure it isnt K jet so maybe I am giving you false ideas. Hope this helped more then confused.