Swapped a 90 b18a into my 89 crx si about a year ago. No other significant engine mods.

Puffing out black-ish smoke that smells EXTREMELY rich. Im getting completely stumped.
Been done:
Plugs, wires, cap, rotor, air filter.

Today I checked the timing... was a little off but its set perfect now.
Still puffing out smoke. It actually seems to smell (if this is possible) cleaner but richer at the same time. Either way, car does seem a little more spunky now but still puffing out smoke like non other. Exhaust is rich enough that it burns my eyes.

Only other thing that I can think of is the cat. My old engine was burning a lot of oil and now Ive been running rich for awhile.
Could the cat be causing THIS much of a problem?
Any other suggestions would be VERY welcome.

 

had a similar problem with my b16a. it was a vacuum leak - the pcv valve was broken. a malfunctioning fuel pressure regulator could also cause the engine to run rich. suggest you look for vacuum leaks and check the fuel pressure. r u getting any cels?

 

I have noticed Ls engines run a little rich after about 75K ... I have no idea why But if there is no air leak then you can get a fuel regulater

 

Thanks for the info. There is a chance of a leak... it would have to be a tiny one though. Any suggestions on how to find a tiny leak? Ill see if I can figure it out.
I have a crx meet this weekend so I am hoping to get it taken care of by then, but if not I do plan to get a FPR when I get back.
A little while ago it was throwing an O2 code but I was burning oil then. Replaced valves seals and such and it went away. I have reset the ecu since then.
Thanks for the input, Ill let ya know what happens.

 

 

A way to find a vac. leak is to get some Carb/Throttle body cleaner or brake cleaner and spray every hose and part on the intake man. to see if there is a leak.
You will hear the engine start to die or the rpm's should drop a little and when they do You have found your leak.

 

A way to find a vac. leak is to get some Carb/Throttle bado cleaner or brake cleaner and spray every hose and part on the intake man. to see if there is a leak.
You will hear the engine start to die or the rpm's should drop a little and when they do You have found your leak.

 

well... no leaks... so back to the drawing board