I searched to no avail, so here is my problem...

My car is a '90 tII, which is bone stock, just to clarify. I have antifreeze leaking from somewhere around the intake manifold area. The sensor on top of the radiator was loose, and there was coolant pooled up under the intake there...but the intake filter is dry and clean, so nothing got in there. I can't tell if it just leaks down from somewhere up top, or what. Plugs are dry, and other than looking like they should probably be changed, are good. Since the coolant leak has gotten worse, I have been experiencing problems with my idle. The car starts fine, has no cold start or hot start issues. It will idle fine until it gets fully warm. Then, the idle bounces really bad, and the car chokes and dies. Starts back up fine after it dies though. Can't find any vacuum leaks, but I haven't checked all sources as of posting this thread. When driving, the car pulls boost and doesn't seem to have any loss of power.

I was just wondering if there might be any emmissions crap or something other than a vacuum leak somewhere that might be the culprit?

I would like to think that if something were wrong with the motor its self, then it would show other signs of weakness such as coolant in the oil, loss of power, overheating, hot start problems, etc...but nothing. Just the stupid annoying idle and coolant leak I can't seem to locate.

Any suggestions?? Sorry for the long post, just wanted to explain in detail for better diagnosis!

 

coolant leak: I would suggest looking at the hoses going into the throttle body, and to the BAC, judging from where you say the leak is. There are a couple of nasty bendy hoses in that area to look at that may have come loose, split, just got old and corroded, etc.....

idle: I'd check out the TPS, check out the connections to the battery, and search again for vacuum leaks per the compressed air method (best one....) there's a thread by NZconvertible on that... pretty simple, just intstall a female air connector to a 2" (? whatever the stock turbo intake is.... I think 2" anyway) PVC cap, get some way to seal that connection, and regulate the air from the compressor and bam.... within about 5 psi you should hear some leaks if there are any.