Ok, so I have a 96 prelude si , and the piece of crap plastic tank radiator cracked on the top just like my 93 si did. So me and a friend replaced the radiator with a slightly thicker, all metal one. We get everything disconnected, plug the new one in, replace the tranny fluid that leaked, check all fluids..... etc.

Now I drove it for a bit, seemed fine. After about 5-15 minutes of driving the car has an extremely rough idle when I'm in D4/D3/R at a stop. The rpms drop to about 3-400 and almost dies..... I rechecked the transmission fluid and it seems perfectly fine, I've also let air escape from the radiator numerous times and topped off what has leaked from the top with the cap off....

Please advise... Thanks

 

You may still have air trapped. Make sure that you have the overflow tank filled up and keep bleeding the air out.

 

yep, bleed the system