Skip to main content
Topic: Still can't pass emission testing (Read 1437 times) previous topic - next topic

Still can't pass emission testing

I found the problem with my idle, replaced the ISC assy, and the car is running MUCH better. I was impressed with the difference this made. Seemed so logical after beating it around for a week.

However, emissions testing is killing me. I have replaced the EGR valve and sensor after getting a code, have driven approx 600 miles with high octane fuel and additives to clean the carbon deposits, yet I still have no improvement at all with the level carbon monoxide in the exhaust and very little in the level of hydrocarbons. I posted before that the car had been sitting for a long time, and knew it would need help, but want replace whatever is necessary to begin with before looking at the things that are going to need attention soon.

My question(s)...O2 sensors, cat convertor, or both? Any other thoughts as to what may be the problem? Most everyone tells me to replace the cat converter, but haven't had it to a mechanic yet. I know both O2 sensors and cat converter are pita so want to pursue the best chances first. Also, any suggestions with chnaging O2 sensors? I really want to do these myself to get to know the car.

You guys were a lot of help before, I am humbly begging again...

Re: Still can't pass emission testing

Reply #1
If your catalytic convertors are in good working order and not clogged there SHOULD be no reason to replace them....You'll know if they are clogged up or broken...You'll step on the gas and almost nothing will happen.  It'll feel like she wants to give you more, but can't.  As far as the O2 sensors they are not a difficult task as far as know how goes.  What IS difficult is getting the old ones out 'cause 9 outta 10 times they are rusted/frozen into place.  Spray them down with some WD-40 or liquid wrench or some other equivalent.  Run the car for about a minute then see if they will come loose.  Oh yeah...Don't touch any metal on your exhaust after that with bare skin.  It will most likely be "warm" :flame:
Good luck and hope you pass emissions without driving yourself crazy ;)
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Re: Still can't pass emission testing

Reply #2
It is responsive when I ask for more, and if not for the emission thing, I would be pretty satisfied with the performance. To read everyone's comments, I can't ask for a lot from stock 3.8 anyway.

I will replace the O2 sensors this week and if she feels better. If not, I'll try to get a waiver and pay for a complete diagnosis test. I can think of many ways to better spend the $65 just for the test. Afraid of what else I may find out.    :bricks1:

Thanks for the help...
Dave

Re: Still can't pass emission testing

Reply #3
Hey...one other thing, if anyone can help. I read something in another thread about a specific O2 socket for removal. Any idea where I can get one or if it will help?

Re: Still can't pass emission testing

Reply #4
You can rent them from Vatozone for about 15 samolians.
Temporarily Foxless? Ride the Bull...

Re: Still can't pass emission testing

Reply #5
Should be able to get the socket at A Zone or Advance, etc..

Are you using premim gas for the emissions testing???? If so thats a big NO NO, run regular as it burns quicker and cleaner... Also has the OIL been changed lately??? Believe it or not contiminated oil can contribute to high emissions... Lastly is the timing set correctly??? too much advance can also cause probs..

Re: Still can't pass emission testing

Reply #6
Put some ethanol in the tank for the emissions test.

 

Re: Still can't pass emission testing

Reply #7
Changed the oil as soon as I got it home, first thing. Timing is at 10 BTC, which is what I have been reading as the best setting. I was using high octane to begin with, but used 87 for awhile before testing. Should have been 'cleared' of the premium.

I had plans to change the oil again once I got it together, but will change it before running through next week. The old oil was in baaadddd shape and I want to run a couple clean passes through it.

ethanol...I was told a bottle of rubbing alcohol by one person, also had another sware that he places 3 or 4 moth balls in the tank before testing (never heard this before though).