Emissions Dyno Run Graph. FAILED Help
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Senior Member
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Joined: Oct 2003
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From: IL
Car: 91RS_92Z28
Engine: 5.0_5.7
Transmission: WCT5_WCT5
Axle/Gears: 3.08_3.42
Emissions Dyno Run Graph. FAILED Help
LO3 stock 5 speed
IL Air Team emissions test results
Here is the IM240 RDR graph
http://community.webshots.com/photo/...34791802uhVJVw
CO= 0.84 gpm = FAIL Pass= .80 gpm
NO = 7.2 gpm =Pass Pass= 15.0 gpm
CO2= 479.4 gpm Pass =N/A (doesn't apply to 91s)
NOx= 2.50 gpm Pass =N/A
From the graph it seems as if my HCs, Cos, and CO2s are spikeing when the shifts are made, not really apparent on graph though. I'm thinking something in the emissions controls system that changes/switchs with acceleration and deceleration.
What are the problem areas i should look at?
BTW: 1/2 tank of 87 Octance with 3 bottles of HEET when tested
Parts replaced before test:
Delco plugs
Coolant flush, Upper and lower radiator hoses, 185 Thermostat
Oil Change
Bosch O2 sensor
TBI throttle plates sprayed with STP cleaner
Parts changed 8K ago:
Cap and rotor
MSD Wires
Cat and back exhaust (catco/dynomax)
Engine is stock.
I can push the diaphram on the egr freely.
Car feels strong runs smooth, a little rich.
Sometimes it surges a little at idle, but rarely.
Slight puff of smoke on start (been that way for 100K)
No idea as to the timing yet.... Last set to factory 0 deg a while back
No trouble codes stored
Trans has syncro and clutch adjustment problems, at times (Which the Air Team kid dyno drivers are making hella worse. (My T5 & I are1) They can't seem to even find the p brake let alone friction point. arrrghh
I really need to pass, my license is at stake.
(driving a w/o 3rd Gen or any car in general will hurt really bad)
Those spikes during shifts are way to high. sup with that?
IL Air Team emissions test results
Here is the IM240 RDR graph
http://community.webshots.com/photo/...34791802uhVJVw
CO= 0.84 gpm = FAIL Pass= .80 gpm
NO = 7.2 gpm =Pass Pass= 15.0 gpm
CO2= 479.4 gpm Pass =N/A (doesn't apply to 91s)
NOx= 2.50 gpm Pass =N/A
From the graph it seems as if my HCs, Cos, and CO2s are spikeing when the shifts are made, not really apparent on graph though. I'm thinking something in the emissions controls system that changes/switchs with acceleration and deceleration.
What are the problem areas i should look at?
BTW: 1/2 tank of 87 Octance with 3 bottles of HEET when tested
Parts replaced before test:
Delco plugs
Coolant flush, Upper and lower radiator hoses, 185 Thermostat
Oil Change
Bosch O2 sensor
TBI throttle plates sprayed with STP cleaner
Parts changed 8K ago:
Cap and rotor
MSD Wires
Cat and back exhaust (catco/dynomax)
Engine is stock.
I can push the diaphram on the egr freely.
Car feels strong runs smooth, a little rich.
Sometimes it surges a little at idle, but rarely.
Slight puff of smoke on start (been that way for 100K)
No idea as to the timing yet.... Last set to factory 0 deg a while back
No trouble codes stored
Trans has syncro and clutch adjustment problems, at times (Which the Air Team kid dyno drivers are making hella worse. (My T5 & I are1) They can't seem to even find the p brake let alone friction point. arrrghh
I really need to pass, my license is at stake.
(driving a w/o 3rd Gen or any car in general will hurt really bad)
Those spikes during shifts are way to high. sup with that?
Last edited by srdynamics1; Apr 17, 2004 at 05:11 PM.
Thread Starter
Senior Member
iTrader: (10)
Joined: Oct 2003
Posts: 666
Likes: 0
From: IL
Car: 91RS_92Z28
Engine: 5.0_5.7
Transmission: WCT5_WCT5
Axle/Gears: 3.08_3.42
One more thing. A few weeks ago there was massive oil in the air cleaner. I panicked and posted OIL IN CLEANER!!!. THat problem was cleaned up, but not fixed, as I just replaced the filters. The crankcase breather tube filter is just wet with oil after 300+ miles now.
Could my TBI be junked up? The throttle plates were clean and so were the bores?
Could my TBI be junked up? The throttle plates were clean and so were the bores?
Joined: Feb 2001
Posts: 13,748
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
It could be as simple as your 02. Bosch 02's can make these cars run rich. I know it costs money to get another one but put your stock one back in if it has under 70K miles on it or go get a delco one. That may be your problem. I am looking over the other stuff for you and will get back with you on that.
Thread Starter
Senior Member
iTrader: (10)
Joined: Oct 2003
Posts: 666
Likes: 0
From: IL
Car: 91RS_92Z28
Engine: 5.0_5.7
Transmission: WCT5_WCT5
Axle/Gears: 3.08_3.42
The Bosch O2 probe end was a much larger than Delco O2. I didn't notice it getting any richer after the O2. The old one had to be broken off, so i can't put it back in.
My thousands of searches on the board lead me to suspect the ORIGINAL FUEL FILTER (150K) because apparently they can cause intermitant problems. The car does behave eradically, going from strong to sluggish without any provocation.
Tested again today at a different station and the driver was outstanding. FAILED.
From the graph it seems that the massive spikes that occur in 1st gear when the wheels start to turn the dyno wheels are an indicator of something, what, I don't know.
My thousands of searches on the board lead me to suspect the ORIGINAL FUEL FILTER (150K) because apparently they can cause intermitant problems. The car does behave eradically, going from strong to sluggish without any provocation.
Tested again today at a different station and the driver was outstanding. FAILED.
From the graph it seems that the massive spikes that occur in 1st gear when the wheels start to turn the dyno wheels are an indicator of something, what, I don't know.
Last edited by srdynamics1; Apr 17, 2004 at 05:18 PM.
Joined: Feb 2001
Posts: 13,748
Likes: 560
From: Cincinnati, OH
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
You could be right about the filter. I would replace that anyways. A clogged one can cause you to run lean when driving and can make your HC's go up due to imcomplete combustion.
Supreme Member
Joined: Dec 2000
Posts: 2,375
Likes: 0
From: Tucson, AZ, USA
Car: '99 Trans Am, '86 Camaro
Engine: LS1, Scrap
Transmission: T56, T5
Axle/Gears: 3.42 Stock ZT, 3.42 Open
The oil in the air cleaner indicates a clogged PCV system.. pull off the PCV valve and the PCV hose at the throttle body, and make sure both flow, then depending on how you feel about causing your motor to burn sludge, take a small screwdriver (as a pick) and throttle body cleaner and clean out the PCV port in the throttle body with the engine running, or pull the throttle body off and clean up the port.
Clogged PCV can cause slight miscalculations in open loop AFR since the system expects to be pulling some air in through the PCV port, but its impact on closed loop operation should be minimal.. *might* be enough to bring your HC emissions into spec though.
Clogged PCV can cause slight miscalculations in open loop AFR since the system expects to be pulling some air in through the PCV port, but its impact on closed loop operation should be minimal.. *might* be enough to bring your HC emissions into spec though.
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