89GTA5spd

The guy at the smog check place said that my car was way over the limit of NO.. and said it was probably my EGR... but it was way over. I went to a place that had the dynometer kind of smog, but I am going to go out of county and try it at a place that doesn't have that. (my car isn't registered in san diego.. it's registered where smog II isn't required)

Does anybody know if it is definately the egr? or how i can test the egr ? The little vacuum tube connector on my egr solenoid is broken, so I think it's that.. but would that really make me fail.

Also, my exhaust kind of has a gas smell to it, so I think it might be more than just the egr not working.. i think it is running really rich.

Any help or suggestions welcome.

89GTA5spd
Flowmaster Cat-back, Intrax springs, KYB Shocks/Struts, AFPR, Ported Plenum, K&N ...

Ray87Z

What is your cat setup? Both of my cars failed miserably on NO (triple the limit). But I had gutted cats on both cars. The addition of a catco 3" cat on both and NO dropped to near non-existant levels.

The 87Z has ZERO smog equipment on it other than the catalytic converter. No egr. The 86 IROC has the EGR on there along w/ the cat, but nothing else. I think the air system is somehow tied in w/ the EGR so I doubt it is functioning (but I don't know, could be wrong).

If you're running the stock cat I'd question how well it's functioning. I'm sure it could be tuning, don't know about the EGR. Just sharing my experience w/ NO levels. They were related 100% to the presence of a functioning cat on both of my cars... Testing was all on the New IM 240 or whatever dyno test. My 86 IROC had passed the standard idle/rev in park test with the gutted cat still in place last time, but not the dyno test...

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Ray87Z
-Vortec headed 350.
86 IROC w/ a cammed 305 TPI.
Formerly Ray86IROC.
www.inter-scape.com/Ray

[This message has been edited by Ray87Z (edited November 03, 2000).]

Vader

89,

The "gas" odor should have been accompanied by high HC numbers on the sniffer. High NOs are usually due to hot combustion temperatures. If the HC numbers were not excessive, you probably aren't running too rich.

Make sure the EGR is functioning. Check the vacuum hoses and solenoid. Try manually apply a vacuum to the EGR valve with the engine idling. If you have a handheld pump you can apply a controlled vacuum. If you don't, just use the vacuum nipple for the FPR to apply vacuum to the valve. The engine should stumble and probably will die with full vacuum at the EGR while idling. This would mean the valve is functioning properly.

Take your car out and get it drunk (lots of alcohol). The alcohol will help lower combustion temperatures and NOs. You might want to even try "cheating" by advancing the timing a bit more to coax better combustion before the exhaust valve opens. Just don't do any heavy accellerating on the dyno so the EST retards the spark.

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Later,
Vader
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"Make Me Bad"
Adobe Acrobat Reader 4.0

MY87ROC

hey 89gta5 are you getting a code 32 egr fault it will cause high NO, also can cause rich condition because if that vaccume tube on the egr valve is broke you should have a vaccum leak, is idle a little rough and maybe low? GMTech wrote a very good tech article on code 32 (egr) it might be in tech section on this board it is very informative on the funtion of the egr system.

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TPIS airfoil,relocated MAT,AFPR,TB h2o bypass
otherwise stock 5.0TPI
700r4, 9 bolt 3.23 g92 axle

Omar

89GTA, La Jolla, huh? Scripps Ranch here. Did you get tested in your area? Believe it or not, if you go further south, like in Chula Vista, they are willing to "tinker" with it to help you out. Mostly what these guys already mentioned. If you are not registered in an enhanced area, you should of taken your car to a regular smog station with no dyno. Again, Chula Vista...

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1989 IROC-Z 5.7L

89GTA5spd

I live in University City.. go to school in La Jolla (UCSD). I am going to take my car down to chula vista tommorow and see if it will pass the non dyno test. If it does, i think i am going to take my cats off (dual cat setup). I am afraid if it is my cats cause dual cats would cost me around $300 to fix.

I'll change my timing (set at stock right now) and see if that helps too. Today I'll try that trick to test my egr valve.