CEL Comes on then Off

[baggiestpanther19]

Hey guys, I have this weird thing going on in my MX, the CEL is usually off now, but sometimes (and I can't base it on anything specific, like it only comes on when I'm doing this speed for so long or w.e) it comes on, and then a little while later it'll turn off by itself. I TEN and GRD the diagnostic box, and I get codes 17, 41, and 46, or EGR, VRIS1 and VRIS2. Everything seems to be wired up properly though, there's no way the connector for VRIS2 will reach the connector for VRIS1, and the same goes for the vacuum lines. So I'm stumped...is this maybe because of the 94 ECU running my 93 wiring harness?

Somewhat unrelated, it sounds like I have an exhaust leak or the exhaust is very restricted, sounds like either
a) lawnmower
b) shitty Honda
I've tried to locate the leak underneath, I can't feel anything when the cars running. I think it's the flexpipe before the cat though, for a few reasons. I can smell burnt gas when I cold start it, and sometimes when I'm driving, and cat is covered in black, I mean it is BLACK. But, when I put my hand around it when the cars running I don't feel any exhaust leaks. Is it possible for the flex pipe to be broken on the inside and the mesh on the outside to be fine? Or is it my cat that's broken? Can anyone help confirm that it's the flexpipe or the cat? I'm pulling my hair out here (what's left of it anyways) after Speedy spanked me with a 900$ bill to change exhaust manifold gaskets and do an alignment. A flex pipe replacement would be an easy fix though, and relatively cheap, so I wanna make sure I change the right part. A cat swap would be easy too since I have a Magnaflow high flow cat just sitting at home waiting for some love.

[mitmaks]

I found exhaust leak by taping shop vac (to blow air instead of sucking it) into the exhaust/muffler and then I sprayed suspicious areas with soapy water. Wherever you have and exhaust leak it will bubble up.

[baggiestpanther19]

Genius...just f---ing genius!!! Well I need to get a shop vac anyways, maybe I'll give this a try! Thanks!

[Daninski]

Are you kidding us $900. I'd say there's some thing rotten in Denmark.

[baggiestpanther19]

I'm not kidding you...it was a 900$ bill. I almost had a heart attack. Needless to say I'm NEVER going there again to have any work done on the MX