Jet Black

--update--

Car passed emissions _barely_. I replaced the cat, O2, plugs, rotor, wires, cap, rotor, did an oil change, swapped FPRs with one from an 88, cleaned the injectors with carb cleaner and compressed air, did a seafoam cleaning and adjusted the valves and changed the PCV

The car now burns richer than it did before (soot builds up faster) AND takes more gas. For gods sake, I just tuned it up.

What can I do?
-----


Long story short, my car is wired MPFi but I blew the engine and the only option was a d15, so I converted it to MPFI to get myself out of a jam.

I've done about 20000km on the swap and noticed allot of carbon comming out of the exhaust. I've failed emissions with CO and HC way too high....NOx was bearly leagal, values:

http://www.clubintegra.ca/yabb...=5893

Since then I've cleaned the injectors, done a seafoam treatment, changed the cat, plug O2, cleaned the air filter and changed the PCV valve.

While changing the cat I noticed that the exahust pipe was caked with carbon buildup on the inside, about 1mm thick.

Istn't it normal for a MPFi swap to run rich as it's getting more fuel than needed? If so, what have you Cali guys done to fix this? I've thought of pushing timing up a bit, but dont know how much.


Modified by Jet Black at 3:39 PM 11/20/2006

thesmogman

Could be a couple of things.... Of course.
HC and CO When HC and CO are up it usually means poor combustion.
With the poor combustion the HC's are not burned and come out the exhaust with the partially burned GAS which equals CO.
Cap, rotor, and plugs would help poor combustion.Timing also could be an issue. Here in CA we are required to be at spec +or- 2 degrees. I would stay at spec.
Run 87 octane it burns easier (forHC and CO) and at lower temp (To help the NOx)
Also when you did the test, how old was the gas and did you add any additives?

Another thing is the ECU applying to much fuel??? wrong ECU? (I have not done any swaps so I don't know)and or fuel injectors. This is just a maybe.
Someone else help!

Could also be a valve adjustment. If you have valves not opening properly it can lead to poor combustion.

Start checking these and see what you come up with.

Jet Black

Hey man, thankls for the reply!

The gas was like 1 day old and had no additives, the cat had also been heated up for a good 1/2 hour.

THe thing is the car has an MPFI swap, its a d15 block which is normally 2 fuel injectors, dual point fuel injection, that has a civic Si d16 intake manifold, ECU and distributor. The Si manifold runs 4 fuel injectors, and I'd assume would deliver a bit more fuel than the d15 since the d15 has a larger volume (allbeit not much larger).

I guess I could work on the plugs and rotor, what's odd is my timing light isnt allways gooing off, which is like its not picking up the spark, however the light is cheap chinese one and I dont detect a change in the engine when ti doesnt go off.

I'll work on the timing and do a valve adjustment as I have no clue when it was ever done.

But I think the underlying problem would be that the ECU is applying too much fuel.

thesmogman

Yeah, That is where I was going with that.(ECU)
How old was the cat when you had the test. It usually takes a couple of days for the cat to be it's most effective.
87 octane right?
I was thinking about your coating of the exhaust, Did the old motor burn alot of oil?
Might be the build-up was from then.

Jet Black

Nah, I've only been on that exhaust pipe for the last 2 months....long story short, I took the civic across canada and had allot of "events".

That pipe was used, so its possible that it had all that carbon before. The original cat broke off the pipe, it was easier to replace the cat and pipe at once as I had spares.

The old cat never smelt but would run rediculously hot, meling the tar off the floorpannel. When I pulled it I noticed it was plugged. I installed another cat at that point, which I could see quite clearly through. The car smelt like *** after that. I had it like that for about 2 mothsn then went for emissions test and failed. At that point I picked up a new cat which I installed last night (thats when I noticed all the carbon)

I'm hoping that after dooing all this maintenance I'll pass, but I still think that having the fuel maps off (even tho its like 8%) might be enough to expletive me over.

I'm surprised that you'd think its the wires/cap/rotor....I thought that when you'd have ignition problems like that you'd notice hesitation.

Jet Black

le bümp

janz3n

iv got the mpfi on a d15b2 and i get carbon on my bumper all the time. it was etested in the summer. i didnt do it but it passed.. dont know if the guy that idd it got it done by someone he knows and didnt actually pass. but im in canada.. and i think any honda witha good cat can pass saftey.lol. i would just say its timing or something i dont know.

Jet Black

bump

see update