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The hell that is Texas emissions

Well, failed again.

I took the car in for a new cat hoping to cure the emissions problem.  So far I’ve replaced just about everything else so it has to be that right?  Wrong.

This time I only failed on the low speed Nox.  Passing is 1184 ppm and the car ran a 2557 ppm (FYI on the high side passing is 1082 and the car scored 725). Doesn’t it seem strange that the low Nox is THAT much higher?

In addition to the cat I’ve replace the EGR, had the throttle body cleaned, replaced the O2 sensors, plugs, and wires.

The only feedback I got was that I should drive it for 50 or so miles and we can try it again, but since it was so bad the old guy said he didn’t think it would bring it up to passing.

He mentioned that he didn’t think the EGR might be getting the proper vacuum? Any suggestions on tracking this problem down?


Thanks.

Re: The hell that is Texas emissions

Reply #1
C'mon people!


What good are you to me?

Re: The hell that is Texas emissions

Reply #2
that's a lot of nitrogen...I'm curious what the problem is if it isn't the cat or egr. Is there even anything else that'd lower the nitrogen levels besides changing fuel?
1988 Thunderbird Sport

Re: The hell that is Texas emissions

Reply #3
yea that's what's weird.  It passes fine at high speeds, but is almost double the limit at low.

I need to check out this whole vacuum a the egr thing.

Re: The hell that is Texas emissions

Reply #4
In my state it says that if you have spent $200 or more on your car, in emissions related repairs, then you are excluded from it. :headbang:
You should check it out, i think that mine said somewhere on my emmsions papers.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Re: The hell that is Texas emissions

Reply #5
u may want to look int paying like 75bux and buying a sticker, or um... finding one :2c:

Re: The hell that is Texas emissions

Reply #6
The thought has crossed my mind, but let's just say my present employment makes that not such a good idea.

Re: The hell that is Texas emissions

Reply #7
OK I’m pretty sure it’s the EGR.  It seems like it’s not creating any vacuum at low speed.


Has anyone had this type of problem before.  I just had the EGR replaced so it must be a bad connection or something.  Trouble is I only have a couple of days to get it reinspected.


If you’ve had this type of problem before I’d appreciate haring about it.

Re: The hell that is Texas emissions

Reply #8
well, i had a similar problem in a 3.8 i used to have. turned out to be a map sensor. all i can realy tell you is that emissions blows. the (new) emissions in MA is much like Ca i guess. the put your car on a set of rollers much like a dyno and test your car at different engine speeds with a load on the engine. it was supposed to make it harder to pass but in some cases ive seen it help. massachusettes blows goats in my book. this state is a joke in all kinds of instances. aspecially with gun control. thats for another day though. anyway....i wish i had more input on your problem man. sounds like it could be vaspoogee i guess. good luck
:america: 1988 Thunderbird Sport, Former 4.6 DOHC T56 conversion project.

Rest of the country, Welcome to Massachusettes. Enjoy your stay.

 
Halfbreed... Mango Orange Y2K Mustang GT
FRPP complete 2000 Cobra engine swap, T56 n' junk...
~John~

Re: The hell that is Texas emissions

Reply #9
never mind.  Found it.

Re: The hell that is Texas emissions

Reply #10
Borrowed from another web site:

Emissions Repair Tips
CO too high = Car runs rich, burns too much gas.
Bad carburetor adjustment, float too high, carburetor flooding, sticking secondary throttle, leaking fuel injector, leaking fuel pressure regulator, feedback system malfunction (oxygen sensor, coolant sensor, throttle position sensor), emissions vapor system malfunction (purge valve, canister clogged) Be aware that NOX will RISE after you fix a CO problem. This must be checked after a successful CO repair.

HC too high = unburned fuel in exhaust; car runs very rich or very lean. This is the trickiest condition because there are different causes. If the car is running rich (high CO), the HC can be high also. If the CO is very low and HC is high then the vehicle has a lean misfire.

If The CO is high, fix that problem first. If CO is low and HC is high look for engine skipping, misfire due to vacuum leaks, ignition timing set too high, ignition problem (plugs, wires, cap), carburetor adjusted too lean, leaking egr valve. If you can’t find a reason for the high HC then perform balance test then compression test.

NOX too high = NOX forms in normal combustion. NOX too high indicates high combustion chamber temperatures or malfunctioning post-combustion emission controls.

CO and HC must be normal before attempting to repair NOX failure. Anything that can create high combustion chamber temperatures will make NOX reading high. Engine overheating, air cleaner hot air door stuck closed, egr vale not functioning, clogged egr valve passage, lean fuel mixture, ignition timing set too high. The two main systems that reduce NOX on a car are the egr system and catalytic converter. If your car is pinging, the NOX will be too high. Pinging is a symptom of high combustion chamber temperature. If all the test readings are just a little too high (slightly high CO, HC, and NOX) it is likely the catalytic converter is damaged or empty. If your converter is supposed to have air injection and it is disabled, the converter will not function properly.

Re: The hell that is Texas emissions

Reply #11
I PASSED!!!!!!!!  :hick:


barely.  :wtf:



Low speed Nox passed by 24 points.


Thanks softtouch.  I obviously still have a problem, but at least now I can drive it while I work on it.

Re: The hell that is Texas emissions

Reply #12
might try clearing the codes just for S&G's...

Methos

Re: The hell that is Texas emissions

Reply #13
FYI: Another popular cause for NOX failure is ignition timing being set too high. A trick is to retard the timing a couple degrees even lower than what the factory calls for. We're in the same boat here for E-testing (every 2 years) and have the same test....a 40km/hr(25mph) rolls test and then a 2 min curb idle test. Most people seem to struggle on the curb idle test. I recently had the monster tested for my plate renewal aand was tested to the standards of the original 2.3 turbo (marginally tighter than a V8) Passed with flying colors and plenty of room to spare:

Results:

40km/hr (25mph) test Readings:

HC ppm= 20 (limit= 109)
CO%= 0.00 (limit= .061)
NO ppm= 295 (limit= 1206)

Curb Idle readings:

HC ppm= 29 (limit= 300)
CO%= 0.00 (limit= 1.5)
NO ppm= N/A (limit= N/A)

Specs on the car for those that care:

306 ci, AFR 165's, E303 cam, Edelbrock Performer Intake, BBK 70mm TB, 42lb/hr injectors, Pro-M 80mm MAF, Paxton AFPR, Paxton Novi 2000 Supercharger, BBK Shorty Headers, MAC 2.5" Catted H-pipe.

Tune specs:

Electronic Tuning via PMS ( -12% fuel @ idle)
Fuel pressure: 42lbs vacuum off
Timing: 13*
Fuel: Sunoco Ultra 94
Engine temp during test according to the AutoMeter gauge: 178* F

Re: The hell that is Texas emissions

Reply #14
wish I had the piece of mind knowing that my engine ran that clean...great work
1988 Thunderbird Sport