Need help-car failed emission test
Thread Starter
TECH Apprentice
Joined: Nov 2001
Posts: 324
Likes: 0
From: Fort Worth
Need help-car failed emission test Since the last inspection,I have installed a T-1 cam and FLP headers with cats,stock tuning. The low rpm test(hydrocarbons) was real high at 696.I have a HPP3 and a ported maf that I can put on the car. Will that help much? Any suggestions?Thanks
D(irecto)r Pepper
Joined: Nov 2001
Posts: 1,952
Likes: 0
From: Houston Raceway Park...in TEXAS.
Re: Need help-car failed emission test Whoa, before you do all that.
1. make sure the car is fully warmed up.
2. New oil in the crank case?
3. new plugs?
4. The ported MAF "should" lean it out a bit and that will help you some.
5. Set your idle up just a bit..(use a piece of tape, adjust the screw, etc...)
6. Your O2 sensors could just be going bad. LOTS of times when headers are added to a car.. the sensor go bad. This is usually because they got some "bad" substance on them while they were out of the car. Such as ANYTHING with silicone in it, or grease ... man it seems almost ANYTHING will contaminate them. If you can install your rear O2 sensors in the front and give it a go.
They also make an additive that will ower your emissions. It really does work. About any parts house sells it.
Good luck.
1. make sure the car is fully warmed up.
2. New oil in the crank case?
3. new plugs?
4. The ported MAF "should" lean it out a bit and that will help you some.
5. Set your idle up just a bit..(use a piece of tape, adjust the screw, etc...)
6. Your O2 sensors could just be going bad. LOTS of times when headers are added to a car.. the sensor go bad. This is usually because they got some "bad" substance on them while they were out of the car. Such as ANYTHING with silicone in it, or grease ... man it seems almost ANYTHING will contaminate them. If you can install your rear O2 sensors in the front and give it a go.
They also make an additive that will ower your emissions. It really does work. About any parts house sells it.
Good luck.
TECH Resident
Joined: Nov 2001
Posts: 854
Likes: 0
From: san diego ca
Re: Need help-car failed emission test Certain inspectors with ahem, negotiable $cruples can be per$uaded to pa$$ anything - even here in California... <img src="images/icons/wink.gif" border="0">
Make sure your AIR pump is running, even if you have to jumper it on - secondary air reduces HC. Perhaps an oversized pump? Remember, it's reading percentage, so if you double the airflow out the tailpipe, you cut your HC in half...
Make sure your AIR pump is running, even if you have to jumper it on - secondary air reduces HC. Perhaps an oversized pump? Remember, it's reading percentage, so if you double the airflow out the tailpipe, you cut your HC in half...
TECH Senior Member
Joined: Nov 2001
Posts: 8,423
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From: Friendswood,TX
Re: Need help-car failed emission test Make sure you drive it around and get it nice and warm before the check. And $$$$$$$ and <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" /> works wonders. <img src="images/icons/grin.gif" border="0">
Re: Need help-car failed emission test My cam is similar (221/224 .560/.560). Low idle speed could really be killing you. My car was 275 ppm HC on low speed and 9 on high speed (2500 rpms). My idle was at 750 rpms. Raising it to 900 allowed it to pass.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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Re: Need help-car failed emission test [quote]Originally posted by Firechicken WS6:
<strong>Emissions tests??? I didn't even know we had that in Texas. I've never had it.</strong><hr></blockquote>
The big counties (Tarrant, Dallas, Harris, etc) and surrounding DO have sniffer testing. The smaller counties do not.
-Andrew (smaller county resident - we let all our crap blow in to Oklahoma <img src="images/icons/grin.gif" border="0"> )
<strong>Emissions tests??? I didn't even know we had that in Texas. I've never had it.</strong><hr></blockquote>
The big counties (Tarrant, Dallas, Harris, etc) and surrounding DO have sniffer testing. The smaller counties do not.
-Andrew (smaller county resident - we let all our crap blow in to Oklahoma <img src="images/icons/grin.gif" border="0"> )
Re: Need help-car failed emission test Dave, I may need some of your help, I'm putting some Longtubes on and a B1 cam, this will definitely not pas California emissions, post info here and or email me. Thanks. ~Tony
Re: Need help-car failed emission test Last time I went through the sniffer with my K5 Blazer it was idling low (about 600RPM) for some reason that day and since I had previously removed the CAT, I just stepped on the gas pedal to bring the idle up to about 1000 RPM (test maximum is 1100RPM) to ensure the ECM could adjust A/F based on the O2 sensor feedback and it worked just fine <img src="images/icons/grin.gif" border="0">
Re: Need help-car failed emission test Can't you just get your inspection done in a county that doesn't require it? Do you have to have some sort of sticker saying that you had emmissions tests done? How do they know what county you live in?
Re: Need help-car failed emission test In an emissions testing county you get a green inspection sticker signifying the emissions test pass. In a non-emissions county you will get a red inspection sticker. I currently have a red inspection sticker and drive in Harris county. i haven't got an emissions ticket yet, just two speeding tics. <img src="images/icons/wink.gif" border="0">
Thread Starter
TECH Apprentice
Joined: Nov 2001
Posts: 324
Likes: 0
From: Fort Worth
Re: Need help-car failed emission test I tryed buying a sticker and was told no thanks. Since I have to show them proof of insurance(which tell them what county I live in) I wonder if I can get it inspected out of county?Anyone know? Maybe I should have got the <img src="graemlins/gr_judge.gif" border="0" alt="[judgement]" /> cam. Let me know what you guys think. Thanks
[ December 06, 2001: Message edited by: TexassTA ]</p>
[ December 06, 2001: Message edited by: TexassTA ]</p>
Re: Need help-car failed emission test TexassTA,
How about giving us a full list of all of your engine mod's? Stat and fan settings can wreck havoc with emissions testing. When was the oil last changed in the car? What temp was the car at?
Could leaning the car out with a MAFT, get the hydrocarbon's down enough to pass anyone?
How about giving us a full list of all of your engine mod's? Stat and fan settings can wreck havoc with emissions testing. When was the oil last changed in the car? What temp was the car at?
Could leaning the car out with a MAFT, get the hydrocarbon's down enough to pass anyone?
TECH Senior Member
Joined: Nov 2001
Posts: 11,603
Likes: 0
From: Chi-Town, IL
Re: Need help-car failed emission test Will I pass emissions...and when they do emissions testing what rpms do they take it up to??
I have a MAFT and I could really lean it out....
my cam is a
222/222 .563/.563 112lsa
other little mods are in sig...
I have a MAFT and I could really lean it out....
my cam is a
222/222 .563/.563 112lsa
other little mods are in sig...
Thread Starter
TECH Apprentice
Joined: Nov 2001
Posts: 324
Likes: 0
From: Fort Worth
Re: Need help-car failed emission test I have a 180 degree t-stat and the fans turned on at 160 degrees. I used a stock desreened maf.TR-6 plugs gapped at .038.MSD plug wires. The rest of the mods are in my sig.
Re: Need help-car failed emission test Your insurance has nothing to do with what sticker you get here in Texas. It is where the car is registered. You get a different registration sticker for the emisssions counties. They use that to give you the right sticker for the inspection. I used to do inspections... <img src="images/icons/cool.gif" border="0">
