failed emissions test again
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Joined: Sep 2001
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failed emissions test again
Okay a failed a IL emissions test by being over on Hydrocarbons during the cruising mode of the test, this is where the emissions testers accelerate to 55 to 60MPH and cruise for 30 seconds or so, passing is .80 I was at .89. So I started with the basics, new plugs, wires, cap and rotor. I went back for a retest and failed again, same stats basically.
This car is a 91 z28 (305 TPI) convertible with automatic 28K mileage, mostly stock. Injectors and fuel filter were replaced at about 22k, fuel pressure seems to be close to stock specs. Since the second test I have replaced the CTS since it seemed to be reading lower n resitance than a new one, i also will replace the oygen sensor. Anything else I should be looking at besides the CAT, is it possible the cat to be bad at 28K?
This car is a 91 z28 (305 TPI) convertible with automatic 28K mileage, mostly stock. Injectors and fuel filter were replaced at about 22k, fuel pressure seems to be close to stock specs. Since the second test I have replaced the CTS since it seemed to be reading lower n resitance than a new one, i also will replace the oygen sensor. Anything else I should be looking at besides the CAT, is it possible the cat to be bad at 28K?
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iTrader: (1)
Joined: Oct 2001
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From: decatur IL
Car: 86 iroc, 87 iroc, 89 iroc, 89 formula, 84 supra, 85 trans am
Engine: t\a motor 355 lt1 intake, t56,the works, 89 roc 427 sbc tt project
Transmission: to many to list
Axle/Gears: 9bolt 4:10 in the T/A
ttt
Joined: Mar 2000
Posts: 5,703
Likes: 132
From: Orange, CA
Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
Transmission: Tremec T-56
Axle/Gears: 12 Bolt 3.73
Your cat converter is most likely the culprit. They get saturated, a new one usually will make you pass when you are that close.
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Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
Cam change:TRW 198/210 ,450/.460 114 LSA
Stock TBI manifolds
'85 IROC 3" Cat. back Exhaust
14.94-92.00 mph
SDPC base and "350" Vortec coming soon!
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies
------------------
Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
Cam change:TRW 198/210 ,450/.460 114 LSA
Stock TBI manifolds
'85 IROC 3" Cat. back Exhaust
14.94-92.00 mph
SDPC base and "350" Vortec coming soon!
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies
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