General engine questions/issues that aren't specific to the other categories
By jehprofessional01
#348481 Failed smog twice

Initially failed and needed to adjust timing, repair PCV hose, gas cap and high NO.
Here are those readings:
HC: 49/42
CO: .19/.22
NO: 912/782


Had all of the repairs done and still failed :(
HC: 52/45
CO: .22/.17
NO: 1212/961

Had the fuel filter replace a few months ago, but may be time for a tune up :/



Help please.
User avatar
By egsedanguy
#348487 what year is your car? Have you replaced the o2 sensor? Possible leak near the o2? Also If you have not done a tune up prior to smog then that would be a good idea. New plug, cap n rotor and new wires. Fresh oil and a fresh tank of good gas. I have always ran premium befor smog and I also do a fuel cleaner prior to going to get the injectors clean. Also make sure tires are at the correct pressure. Low psi can cause issues cause they wont roll as freely. 1 trick I use and has worked multiple times( may not every time) is run 5 gal of 91 with 1 gal of e85. I got my last prelude to pass even tho the cat was done. not by mutch but it passed. Just some ideas for ya. Just trying to save ya from a cat.
By jehprofessional01
#348488
egsedanguy wrote:what year is your car? Have you replaced the o2 sensor? Possible leak near the o2? Also If you have not done a tune up prior to smog then that would be a good idea. New plug, cap n rotor and new wires. Fresh oil and a fresh tank of good gas. I have always ran premium befor smog and I also do a fuel cleaner prior to going to get the injectors clean. Also make sure tires are at the correct pressure. Low psi can cause issues cause they wont roll as freely. 1 trick I use and has worked multiple times( may not every time) is run 5 gal of 91 with 1 gal of e85. I got my last prelude to pass even tho the cat was done. not by mutch but it passed. Just some ideas for ya. Just trying to save ya from a cat.


My car is a 1993. I've not replaced the sensor yet as it could be a number of things. Don't want to waste money and time. I think the best idea is to get the tune up and work from there.

Thanks for the info.
User avatar
By egsedanguy
#348489
jehprofessional01 wrote:
egsedanguy wrote:what year is your car? Have you replaced the o2 sensor? Possible leak near the o2? Also If you have not done a tune up prior to smog then that would be a good idea. New plug, cap n rotor and new wires. Fresh oil and a fresh tank of good gas. I have always ran premium befor smog and I also do a fuel cleaner prior to going to get the injectors clean. Also make sure tires are at the correct pressure. Low psi can cause issues cause they wont roll as freely. 1 trick I use and has worked multiple times( may not every time) is run 5 gal of 91 with 1 gal of e85. I got my last prelude to pass even tho the cat was done. not by mutch but it passed. Just some ideas for ya. Just trying to save ya from a cat.


My car is a 1993. I've not replaced the sensor yet as it could be a number of things. Don't want to waste money and time. I think the best idea is to get the tune up and work from there.

Thanks for the info.



Ya start with a tune-up thats the best thing. 1) Its good to do 2) It eliminates the easy stuff. An o2 should be about 70-80$ or get one from a friend that you know works and swap it for the test. :thumb: even if you have a friend with a good cat and swap that on also :thumb:
User avatar
By suspendedHatch
#348509 "Premium" gas is not any better than any other grade of gas. By law it has all the same additives as the other grades. It's a higher octane, which is only a good thing if you have a high compression or turbo engine. The higher the octane, the harder it is to burn. If your engine was designed for 87 octane, and you haven't changed the pistons or added forced induction, use 87 octane.

All the D series and the B18b use 87 octane. The B16 and B18C variants use 91 and sometimes benefit from 93.

Running a higher octane than necessary will sometimes help with NOx but will also raise your HC.

In high elevations, 85 is available but I still use 87 as per the owners manual.

This thread is focused on getting your car running well and legitimately passing smog. There are ways to trick the smog machine, but in the end you still have an engine that isn't getting the most power and fuel economy it should be getting.
By Axix23
#348889
suspendedHatch wrote:Why not getting it running properly instead of cheating the system?

You're not concerned about mileage, power, and longevity? Seems like these forums would be an unlikely place to find someone like that.



While I was on the motor that failed emissions, I was getting 35-38 mpg. Power was decent but it was a JDM d15b so not much power either way. Longevity, motor went to 200k. Finally got rid of it and went with a k series. So I won't be failing emissions anymore. :thumb:
User avatar
By suspendedHatch
#348908 If a Honda engine dies at 200k, something is really wrong. Abuse or neglect. I have a VX with over 300k, easily passes emissions, 49mpg city and no signs of wearing out. I have an 88 CRX Si, also 300k. Hauls ass for a stock D series. Passing emissions is a breeze. These two cars are the 11th and 12th Hondas that I've owned.
By Axix23
#348980
suspendedHatch wrote:If a Honda engine dies at 200k, something is really wrong. Abuse or neglect. I have a VX with over 300k, easily passes emissions, 49mpg city and no signs of wearing out. I have an 88 CRX Si, also 300k. Hauls ass for a stock D series. Passing emissions is a breeze. These two cars are the 11th and 12th Hondas that I've owned.


35-38 mpg and being fast as hell ftw! K > all. :)
By 95coupe_dx
#349372 hey guys I need a little help also. my car failed smog and I have no idea why. here's the readings

15mph/25mph

CO
14.2/15.1

O2
0.6/0.2

HC
182/67

CO
.76/.19

NO
2477/195

the car has a brand new Catalytic Converter, an o2 sensor which is less than a year old, fresh spark plugs, oil, wires, cap, n rotor.

any help would be appreciated.
By Zander
#352906 Just went for an emissions test. I drive a 1993 Honda Civic with a B16A JDM swap. I passed everything but the idle emissions....

My Idle Emissions:
442 HC (Failed)
.69 CO (Passed)
10.22 CO+CO2 (N/A)
7.4 O2 (N/A)
780 RPM (N/A)
By skipperjon
#353792 Ahoy! I didn't pass smog at 15mph wondering if you could point me in the right direction. I'm in California. I'll keep this as short as possible.

Its a 1992 honda Civic 4 door manual with 230,000 miles on it. It seems to run pretty good and it passed smog just before I left and only has 4,000 miles since it passed smog 5 years before. Apparently the Cat is really rusted and I did run some of the 5 year old fuel in it just before the tune up.

My car sat for 5 years without being run as I was living outside the country. I did a few things before smoging it (oil change, valve cover, air filter) . I emptied the old fuel and added higher octane (thinking it might help?) and ran lucas fuel cleaner. I passed on my 25mph but not on 15mph and passed on all of the C02. Also reading doctor google someone said it could be O2 sensor so I replaced that and went from 1800(NO) ppm to 1463 (NO)ppm.

For my 15mph

HC (PPM) = 144 Max 96

Co (%) = .37 Max .59

NO (PPM) = 1463 Max 859

For my 25mph

HC (ppm) = 52 Max 79

Co (%) = .34 Max .51

NO (PPM) = 360 Max 798

Before speculate or listen to others speculate what do you think about the numbers? Also there was a tiny crack on top of the air filter box that I put a piece of tape over and it passed all visuals.

Thanks so much! I really don't want to take it to a mechanic as the car is likely worth less then what a mechanic would charge to fix.