emissions problem

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ok car is 93 del sol. has a 94 acura integra motor. ls. has oxygen sensor and cat for the motor. both are brand new. as in less then two days old. problem is car runs to high of nox. running around 2000 but supposed to be around 900. if i drop my timing as low as i can i can get it around 1600. any more ideas on how to drop it. also i am running a pr4 ecu.
 
ok. i see where you are getting with that. i will try that and c what i get. the only problem that i noticed according to you numbers is the nox got higher a little when you did that. i pass everything except nox. but i will try that. most likely wont hurt to try a little just to see what numbers it will run with that.
 
welp... lets get a little more into this then

do you have your full readout numbers??



high NOx can be caused by high combustion temps... specifically temps exceeding 2400 degrees...
that is usually caused by: high compression, lean mix, or overly advanced timing

its an LS engine, so compression is not the issue
i trust it is a stock map on the PR4, so its not a map problem... the thing to look for here would be vacuum leaks
you retarded the timing all the way and still failed, so id say its safe to say its not the timing either

so im going to say you are not likely failing in the combustion chamber

so where is it coming from?
high NOx is generally a sign of a bad Cat or EGR

the 94 LS engine doesnt have an EGR... so thats not the problem

you said the Cat is new... did you get it up to temp??? you should take the car on at least a 20-30 minute beat ride before testing... seriously drive the hell out of it... you want to get the cat good and HOT so that it actually works
 
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welp... lets get a little more into this then

do you have your full readout numbers??



high NOx can be caused by high combustion temps... specifically temps exceeding 2400 degrees...
that is usually caused by: high compression, lean mix, or overly advanced timing

its an LS engine, so compression is not the issue
i trust it is a stock map on the PR4, so its not a map problem... the thing to look for here would be vacuum leaks
you retarded the timing all the way and still failed, so id say its safe to say its not the timing either

so im going to say you are not likely failing in the combustion chamber

so where is it coming from?
high NOx is generally a sign of a bad Cat or EGR

the 94 LS engine doesnt have an EGR... so thats not the problem

you said the Cat is new... did you get it up to temp??? you should take the car on at least a 20-30 minute beat ride before testing... seriously drive the hell out of it... you want to get the cat good and HOT so that it actually works


im currently not at home so do not have the paper next to me. but i did drive for about 45 min just to make sure it was good and hot. has correct map sensor. the part that i am confused is, as i posted on here before not sure when exactly that i had another ls motor in the car. it passed no problems. was the b18b. the motor in now is the b18b1, best of my knowledge not a big difference. this one seems not to pass. car has no vacuum leaks. well let me correct myself. has one very little one where my vac / boost gauge is hooked in. but so little not noticeable. i will post picture or stats of what it did run when i get home.
 
dirty or clogged injectors?

check your plugs... do any of them read "lean"??
 
injectors are clean. i have ran some of the fuel system cleaner. not sure if that would mess with it. but that was about 2 tanks ago. but one plug does look just a little lean. but not much.
 
Seafoam can clean things up but you need to investigate how to use it. I put a bottle in the gas tank (when I filled up) and went threw the whole tank.....then put new gas in and I passed (new O2 and cat). I did not know the B18B1 had no EGR :shrug2:

Seafoam can go in the intake manifold too (with car running) but you need to read up on how to do it safely. You can even put it in the crank case (w/the oil) but its a detergent and you would need to change the oil after you let it run threw the system for a little while.
 
Ok here is a pic of the sheet.
309538_1951494023245_1119450048_31641896_3099228_n.jpg
 
Just checked all plugs again. All are white for signs of lean. I am getting 44 psi after the fuel filter tho.
 
Ok. Got the car to pass. Changed converter twice. Changed intake. Ran Seafoam. Then changed header. Ran it on emissions each time. It went down on nox each time but took all of that to get it low enough.
 
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