I just got my 240 a few days ago, 89 coupe, 180 miles on it. Anyway, though I think the problem may be Alternator but I figure I'd post something.

Idles funky. At first it'll idle above 1500 or so, tap the gas, bumbs but slowly goes down, instead of just droping down quickly. I figure it's cold, so i wait, still idles funny, holding @ 500 for awhile, then rising to 1000, then back to 500. While all this is happening lights and such dim when I press brake/headlights, etc. Few things I could think other than alternator, are grounds or/and tb needs cleaning. Gonna probally do all three since I have to remove some rust anyway. I'll mess with it a bit. Any suggestions would be cool

Oh, on an off note, anyone looking to get rid of a manual tranny cheap, give me a shout

 

sounds like the alt. it's a pain to get out, but you can get it w/o removing anything from below... just takes some finesse!
my alt went out 2 wks ago & my performance went to crap just before it, go to O'rielly's & they have a machine that'll check your whole charging system: starter, alternator & battery

 

It hapened to me to. the engine would go like 450, barely dying, and then go up, then almost die, then go up and so on. Sometimes it would stabilize, and when driving also did what I like to call" double acelerate". When i drove like at 4k rpm and put it in neutral, it would die. Then I took out the mass flow metter(flow metter) and cleaned it with alchol and a very soft painting brush( Bevery carefull!!, it can get broken and its like 300 new, or more), after this, the engine was ideling so smothh, and it ran so gently, I fell like huging it because it runs so nice. In fact. it runs a lot more stable than my fiends 2003 jetta, wich is brand new. so try that. just in case.

 

yeah... ka's purr

 

I'll give it a try
THanks for the advice ^_^
I havent had a chance to work the the girl for a bit, working sucks. Still need to get it legal, need to replace both rack and pinion boots, get both mirrors and find a cheap side marker lens and stuff for the right side. Other than that it should get legal. She was abused bad, but hopefully she'll be reliable transporation for a bit. Plan on getting another mk1 240 (with no rust/no frame damage/decent interior, project basically) to place with and eventually replace this one.