my exhaust broke, so today, i goto the shop. i get my cat hollowed out (since it was clogged horribly), new exhaust, and brakes. im friends with the shop, so i was talking to him, and he said i should see better mpg and HP. i took it around the block and pulled back in and noticed white smoke pouring out of the bay. i thought maybe cause i burn oil and i floored it. so i thought whatever, its not the first time. on my way home, i notice that im blowing white smoke out of the exhaust whenever i stop then go. i also stalled at a stop sign. and whats weird is i have a hollow cat, no resonator, and the fart pipe, yet its quiet, almost like stock. im blowing smoke, stalling, and i hear something rattling. what could this be? and why would it just happen?

 

meanwhile, 2 hours ago, it ran just fine (minus the dragging exhaust)

 

You do know that your cat is built into the exhaust manifold right?

 

No CEL?

 

yeah. its been bad for years now. i figured screw it, while he is working on my exhaust, just hollow it out. he said it would also help me get more mpg. im averaging like 15-20mpg driving like a grandmother.

i had the p0420 code for about 2 years now. now, its throwing up speed sensor codes.


heres what i did. i took it back to him, and told him about how its stalling and smoking. he said the stalling is because of the idle. he turned the idle up and its normal again, no more stalling. He said the smoke is because of the cat. now that it has no back pressure, the computer is telling the motor to add more fuel, and its running rich. he said if i replace the manifold/cat, then the smoke will go away. he also said i need a speed sensor. that threw a cel code. i never noticed it untill AFTER i left the garage, but now, i cant even make it up a hill. its staying in 1st or 2nd gear and wont upshift. so now, i gotta get a new manifold/cat, and a speed sensor, and i guess ill be back to normal? does this sound legit? i mean, i know alot of ppl who run straight pipes, and hollowd out cats, and their car dosent do this. wth?

 

White smoke = coolant from what I know. How's the coolant level in the car?

I am not sure how you hollow out the cat if it is attached to the manifold. I think that is what 94civichb referring to. It is not like a "standard" cat that you can just shove a rod through.

 

If you need a cheap-ish OEM style replacement cat/mani, look on Amazon for a Dorman one. OE spec, works great. Amazon.com: Dorman OE Solutions Exhaust Manifold 674-439: Automotive

 

thats what ppl on hondatech are saying. that the cat has nothing to do with it. but if so, what would cause me to burn coolant just by hollowing out the cat? and no, the cat is built into the manifold. idk how but he showed me the remains, its hollowed out. but somethings weird because hollow cat + no resinator + 2.25" exhaust piping + fartpipe = stock quiet sound??? it just dont make sence, i was expecting to have a headache driving this thing when i got it back.
Edit: Coolant level is fine.


thanks, ill definatly look into it. the one he quoted me is 289. this will save me lots of money haha

 

Replace that cat. I don't want to breathe your damn pollution. And your head gasket is probably shot.

 

the hollowed out cat was just temporary untill i get the money to replace it. it was clogged and not doing its job anyhow, so your breathing in my pollution no matter what. what would cause the head gasket to go bad so suddenly?