MakoE2

Hey I just went to get my 1992 4Door EX tested and I pased every criteria except for

NO ppm limit: 467
My Reader: 1534

Has anyone failed in this category and if so what did you do to fix the problem?

Before the test I got a noil change, pcv valce change, air filter change, oil cleaner all the works and the car only has 142xxx KM on it


Someone said it might be the EGR valve but I dont know much about exhaust systems

Any help would be tremendously appreciated!!

MakoE2

Oh and I also forgot to mention my engine check light comes on after like 4 minutes of driving but then when i shut her off and start again, its gone... then same thing, comes back on after awhile of driving


any clues?

JDMcb7

check for vaccum leaks as well clean your EGR ports

Desslok

What's the rest of the numbers for both speeds? I have had to deal with this issue many times since I always drive POS cars.

Monkey Fing a Coconut

NOx is almost always the EGR system failing, the whole reason for the EGR system is to lower NOx, NOx is caused by high combustion temperatures, the EGR system puts exhaust gases into the cylinder to prevent total combustion to lower temps, if you are running lean it could be one of the reasons you're running hot, cheap fixes are running fuel injection cleaner or changing the fuel filter as not enough fuel may be available, could also be your o2 sensor misreading

best thing to do would be clean out the EGR as it may be blocked from carbon build up

Desslok

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by twistedbydezign &raquo;</TD></TR><TR><TD CLASS="quote">NOx is almost always the EGR system failing, the whole reason for the EGR system is to lower NOx, NOx is caused by high combustion temperatures, the EGR system puts exhaust gases into the cylinder to prevent total combustion to lower temps, if you are running lean it could be one of the reasons you're running hot, cheap fixes are running fuel injection cleaner or changing the fuel filter as not enough fuel may be available, could also be your o2 sensor misreading

best thing to do would be clean out the EGR as it may be blocked from carbon build up</TD></TR></TABLE>

This is all correct. However, if you passed the HC by a wide margin and you have enough room to play with your timing and still be within spec, retarding your timing will effectively lower the combustion temp. That's why I was asking what the rest of the numbers were. If you have an adjustable FPR, boosting your fuel pressure will have the same effect. A clogged fuel filter can cause a lean condition as well. Judging by your CEL going on, I would guess your O2 or EGR is going south. Neither is cheap to replace, but if you have the money, it wouldn't hurt to do a tune up including fuel filter and air filter, replace the O2 sensor if it tests bad, clean the EGR, also drill out the EGR passages on the intake manifold and clean those, then reset the ECU. If after all of that you still don't pass and you are close to passing a new cat will help(speaking from experience).

MakoE2

hey yeah currently i am cleaning the egr ports to remove the carbon buildup

im thinking im going to have to replace the exhaust system soon because its not in the best of shape but it seems to operate fine... so maybe the cat is fucked


im wondering if my 02 sensor is ******* up and thats why my engine light keeps coming onn?


hmmmm


thanx guys for the info keep it coming if you know any more

RotaryBzzzz

if you're stock & passing on HC and CO but failing NOx, it's most likely your 'EGR passageways'. Check out my emission thread below.

Denise Silveira

I failed my emissions today . High hc reading 84 also high no ppm reading 1360 what could b causing this ? I'm a woman & don't know much about cars please help ! Honda accord 1992 exr

Rusty_hoock

MakoE2 have you check for CEL codes that might tell you why your check engine light cames on.

CRX Si69

Yes, we can tell you are a woman. You failed to look at the date of the thread.

Good job bumping a 7 year old thread, 'bro'.

Rusty_hoock

LOLZ

Hidenplanvew

Rusty also failed to look at the date aswell... Im sure he figured it out