I've been chasing a low idle-stall issue on my daughter's 89' 240. Maintenance has been neglected while she lived away at college, so I'm playing catch up...

It still has some hesitation at idle, typically sitting at stop lights foot on the brake, it is an automatic. I have not tried to find vacuum leaks (never had much success at finding those). I have cleaned the flame trap (brass insert from IPD), cleaned the IAC valve, cleaned the Throttle Body - serious Thick oily residue in there - engine intake side. Probably 1/32" thick stuff - I made a couple plastic scrapers to get it out... It did throw an AMM code at one point so I reset & have swapped in a different AMM.

Unrelated (I think?) there may be an electrical issue that causes stalls where speedo needle jerks before engine cuts out. I believe this is the ignition switch because the door open chime is intermittent. Have a replacement switch already to put in.

My question is - what would be the best way to clean this same thickness of build up out of the Intake Manifold? I don't have a chamber/box whatever it's called for blasting - like shot peening/sand blasting... I did find YouTube videos of burning out Diesel intake manifolds. Makes for a cool video but not convinced I want to try a "hold my beer, watch this!" type of show...

Any thoughts? I'm considering getting one from a pick-n-pull and just swap it out.

Thanks folks

Mike
Currently 89' 244 (daughter), 93' 244 (son); my DD 03' Audi allroad 2.7T (Fritz)
I miss these - 88' 245 (Lars); 98' S70GLT (Son of Lars); 95' 945T
I don't miss this one - 98' V70GLT (Bane of my Volvo experience)