1985 Corolla Leaking coolant AND driving rough - any ideas?

[Amerikaner83]

Hello - it's been awhile since I posted last, but I am in need of some advice for my buddy:

He drives a 85 Corolla (not sure of 82 or 86 on engine code, i think it is...),it's a 5 speed, and has about 215K miles on it... and he's got hella problems with it. He can't seem to accelerate at all, wtih any power. I can go from 0 to 60 faster in my bicycle than he can ever hope to go...

His radiator is poltergeisted - it leaks, then he fills it up again with 50/50, then it is OK. A few days later, it takes a leak again. He just told me that he has been using just plain-old water for filling it up the last few weeks..... I know, I know. :P I narrowed down the source of the leak to the radiator, NOT the hoses or anything along those lines.

The damn thing likes to vary idle speed, and sometimes shuts itself off on its own, not to mention a loud, obnoxious squealing noise when the RPMs go above 1500 (that value is just a guess, as he has no Tachometer).

I think the idle problems, and perhaps the lack of anything resembling accelleration, could be due to the throttle positioning sensor, but I'm nowhere near an expert.

Any help from anyone who knows more than me (most everyone here on this froum) is GREATLY appreciated!!!!

Thank you in advance for any and all help, and my apologies for the length of this post.

Michael in Seattle, WA

[joykill]

blown head gasket