EGR line blowing off? Options

[brandon702bmx]

I’ve noticed that my car has been “lagging” to reach high RPMs. Once 4K rolls around, it’s like power just diess out. However, I’ve been experimenting and forcing my car to 5, 6K (slowly, like a steady climb) and sometimes I’m noticing that the line that links the EGR valve to the EGR modulator (the one with the filter) keeps popping off like it’s under pressure when reaching higher RPMs. When it pops off, I can tell because I can hear a hissing noise when accelerating and sort of a “throbbing noise” at idle.

Is this a bad EGR valve? I’ve done the test with the hand vacuum pump connected to it to see if I could kill the engine and it took quite a bit to kill it. It just bogged and ran erratically until I kept pumping it and it eventually died. Haven’t bothered to remove it and see if carbon was caked in it.

Another thing to note is that the car runs a million times better when that hose pops off. Car doesn’t struggle in higher RPMs and runs beautifully. (I’m sure it’s not the brightest idea to run with it off, kind of hard to pull off on the freeway and reconnect it) I had another engine in this car that suffered from the same issue. Completely different EGR valve and all. Still did it. Where do I start...?

Just extra info in case needed:
1994 Celica GT 5SFE manual trans

[Box]

It won't pass visual but it should still pass tailpipe if you get it hot enough before testing, all the pre-cat is for is to heat up the exhaust faster and get emissions as clean as possible as fast as possible. Domestics of the time used smog pumps that served the same purpose, but they injected air into the exhaust for more complete combustion of the exhaust gasses to speed up heating the cat(s) and also helped the cat(s) to work better. Though if both can be cleaned you could just switch to the pre-cat before testing just to make sure you pass.