California Smog test failed

Matt,
Typo my bad, this low impedance injector is 151370 for NSX 95 to 98 3.0 engine and also 96 Prelude 2.2. It is a different part number from earlier and later 3.2 NSX models which use high impedance injectors.
You can't just guess at what size injector to put in. The injector matches the ECU very closely. I assume you are still running the 1995 ECU? I was hoping I could find more information on this injector but I cannot find good solid information other than this same injector was used on 94-95 Honda Accords with VTEC.

I will try to do more research and get back to you later in the morning.

-Matt
 
Something just occurred to me. Did the smog tech disable the traction control before running the test? I think I read somewhere that if you don't disable it your car will fail due to excess HC's.
 
EdinKali,

Thanks, smog tech did not disable traction control. have an OS Giken so there is no traction control. I do occasionaly get the traction control light "TCS is off" in dash board. Pushing traction control button on or off has no effect on the dashboard light.

Stephen

Something just occurred to me. Did the smog tech disable the traction control before running the test? I think I read somewhere that if you don't disable it your car will fail due to excess HC's.
 
Patchez,

Today I purchased the replacement IAT sensor from NAPA auto parts. I measured both sensors cold and they have the same resistance of 3000 ohms at 60 degrees. Now what? Is the Acura book wrong? would you replace it anyways?

Stephen
I would just change the IAT like I said earler in the thread. Forget about injectors for now. The ecu is dumping all kinds of fuel if that IAT is reading 18degrees
 
Patchez,

Today I purchased the replacement IAT sensor from NAPA auto parts. I measured both sensors cold and they have the same resistance of 3000 ohms at 60 degrees. Now what? Is the Acura book wrong? would you replace it anyways?

Stephen

Doesn't that match the book? Are you sure you're looking at the Farenheit scale on the chart?
 
Daedalus,

Took a second look at graph in manual with a magnifying glass using a ruler to see where the resistance curve crossed at 60F degrees. Looking closer I see at the 68F degree mark 2700 ohms or so, it's really hard to see. A table listed of temp and resitances would have been easier to use. So this is not my problem after all. The one in the car and new measure the same cold, will have to measure hot as well just to be sure.

Stephen

Doesn't that match the book? Are you sure you're looking at the Farenheit scale on the chart?
 
Patchez,

Today I purchased the replacement IAT sensor from NAPA auto parts. I measured both sensors cold and they have the same resistance of 3000 ohms at 60 degrees. Now what? Is the Acura book wrong? would you replace it anyways?

Stephen


HHmmm thought you had said it was reading at 18degrees.Ok well what other inputs could it be Map,tps,ect?Theres a list on 11-24 in the manual.It might also be in the wiring so would need to check the signal at the ecu.The computer is dumping fuel because it thinks it needs it.And I would think if it was the injectors it would cause a code as the ecu would be trying to cut fuel and with leaky injector it should notice its unable to.Dose the ecu you you have have a chip?It really sucks trying to read signals on older cars with out a brake out box.Just thought of somthing make sure to check the charcoal canister.Im remembering school once the canister was full of fuel.Im just naming every thing it could be right now sorry.
 
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Might want to hook up a vacuum gauge at this point to make sure the engine is running correctly(ie. one of the camshafts isn't off by a tooth, etc.)
 
Patchez,
Today I decided to find a way to measure the fuel pressure. Found an extra Banjo bolt, drilled and tapped it out with 1/8 in pipe thread then attached an extra engine compression gauge I had lying around. Don't know what I did but now car looses all fuel pressure (0 psi) after it is started. I don't hear the pump running after starting. Starting the engine pressure now drops to zero and stalls. Turn ignition off and on again pressure returns to 42 psi. Turns out FP resistor wasn't plugged in 100% when I moved it to get access to the filter, pressure stays at 42psi now. Picked up two brand new Accell 151370 injectors locally in San Diego for $45 each and have four more in the mail from Craigslist for $37.50. Pays to hunt down parts deals on this car, everything is super expensive! I'm not sure injectors are my problem but at least today I managed to see that the fuel system is operating at the right pressure and tested out FP regulator as well.
Stephen
HHmmm thought you had said it was reading at 18degrees.Ok well what other inputs could it be Map,tps,ect?Theres a list on 11-24 in the manual.It might also be in the wiring so would need to check the signal at the ecu.The computer is dumping fuel because it thinks it needs it.And I would think if it was the injectors it would cause a code as the ecu would be trying to cut fuel and with leaky injector it should notice its unable to.Dose the ecu you you have have a chip?It really sucks trying to read signals on older cars with out a brake out box.Just thought of somthing make sure to check the charcoal canister.Im remembering school once the canister was full of fuel.Im just naming every thing it could be right now sorry.
 

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Have made some progress. Still failing emissions with my car. Last smog check car ran too lean then ten minutes later was back to too rich! Found a certified Acura mechanic at Greenlight auto in Kearney mesa. The Honda Tech Jerry first said I had three bad coils which was odd because they were new Honda parts two years ago. He showed me how to test them and sure enough three were bad! Next it failed inspection and I brought the car back. I talked him into connecting his scanner directly to my car’s ECM. He said it couldn’t be done but I told him there were only four connections 12+, chassis ground, digital ground and K line serial com. I was able to get a connector from a scrapped 2000 Nisan Maxima at a wrecking yard for $5. The Mechanic found out by rigging a connection to his scanner, 3 of my O2 sensors are sending bizarre readings to the ECM, although they are all brand new, they’re defective or miswired. They never change readings while the car is running! I wish I thought of this back in December, the car would have been fixed and registered by now! I wired DLC connector into my NSX. Had a spare 92 parts car harness in a box and was able to keep the DLC connector wires the same color code as there is in the 95 car. This will help me later when working on my car and also the next owner some day. Figured out that I installed the wrong bank secondary O2 sensors in the cats. I swapped sensors with each other and connected them to the correct connectors. Traced out all of the four O2 sensors wiring to the ECM so I know it is wired correctly now. Next is to test the car again. I don’t have a scanner but will buy or get software for my laptop along with a DLC to DB9 converter cable. Wish me luck, have something to do now this weekend. My question is should I buy a scanner? Could also buy a scanner/logger for only about $90 bucks like Equus 3100 Innova CanOBD2 Diagnostic Tool or Memoscan H685 Honda Acura tool. Need something I can make repairs on car with and see results. Some have simulated dyno and emissions tests as well.

95 NSX T new cats are installed but problem prevails.............
Parts installed:
4 new O2 sensors
New PCV valve
New plugs
New coils
New timing belt
New thermostat
New cats
New fuel filter
New fuel pump
New IAT sensor
New K&N air filter
 

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Since you state that the timing belt was replaced did you ever hook up a vacuum gauge to make sure it is running correctly? ie. cam(s) not off by a tooth. It will almost certainly fail if the cam timing is off.

If you don't know how to read a vacuum gauge there is a good reference at:
http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm

A vacuum gauge is a simple but handy tool for diagnosing running issues.
 
Thanks but that is the first thing I tested along with compression. Had a certified Acura tech check that too and he said it was good. Today I finaly hooked up an ODB2 scann tool. Nobody supports Honda/Acura because the SAE standards are for protocol and voltages for the J1962 standard connector but Honda/Acura does not use the Standard SAE pinout like other car manufactures. The ODB2 specification leaves it to the manufacturers to assign unspecified pins for their use. Honda/Acura uses these odd pins for their ISO K-Line serial buss (pin 15, SAE dictates pin 7), Chassis ground (pin 12 SAE dictates pin 4), Signal ground (pin 13 SAE dictates pin 5) and 12+ vdc (pin 8 SAE dictates pin 16) Because my car did not come with any connector I disregarded Acuras proprietary pinout of standard ODB signals and installed a J1962 connector with SAE pinout. Now any standard scanner that supports K - Line ISO 9141-2 communication will connect to ECM with readable information and more. Have switched the back two O2 sensors, just have to run a live test to see what they are reading.

Pin Definition (SAE standard)

1 Not defined
2 Bus positive line of SAE J1850
3 Not defined
4 Chassis ground
5 Signal ground
6 CAN(H) ISO 15765
7 K line ISO 9141/14230
8 Not defined
9 Not defined
10 Bus negative line of SAE J1850
11 Not defined
12 Not defined
13 Not defined
14 CAN(L) ISO 15765
15 L line ISO 9141/14230
16 +12 volt battery

Since you state that the timing belt was replaced did you ever hook up a vacuum gauge to make sure it is running correctly? ie. cam(s) not off by a tooth. It will almost certainly fail if the cam timing is off.

If you don't know how to read a vacuum gauge there is a good reference at:
http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm

A vacuum gauge is a simple but handy tool for diagnosing running issues.
 

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Did the Scan last week and came up with some bizzare readings. Hooked up the scanner and recorded the data. Ran the car about twenty minutes in my driveway. The attached text file shows the car going from open loop to closed loop, partial to fully closed loop to drive open loop and finally fully closed loop . Not sure why, looks like there may still be a bad O2 sensor but which one? O2B1S1 voltage is all over the scale, which bank is this one? Because some of you have more experience than myself, maybe you can interpret the data and give me a hint. Would appreciate any comments or suggestions.

Stephen

Last recorded entry:

DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 35.7
ETC(°F) 178
SHRTFT1(%) 43.0
LONGFT1(%) 0.0
SHRTFT2(%) 43.0
LONGFT2(%) 0.0
MAP(inHg) 7.4
RPM(/min) 3426
VSS(mph) 0
SPARKADV(°) 50
IAT(°F) 97
TP(%) 15.7
O2S B1S12--B2S12--
O2B1S1(V) 0.000
SHRTFTB1S1(%) 43.0
O2B1S2(V) 1.040
SHRTFTB1S2(%) 43.0
O2B2S1(V) 0.360
SHRTFTB2S1(%) 43.0
O2B2S2(V) 1.020
SHRTFTB2S2(%) 43.0
 

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It if were me. I would use an ohm/volt meter and read the voltage directly at each of the O2 sensors and watch for erratic readings. You may need to use an analog volt meter as it may change too fast for some digital meters.
 
I don't have an analog voltmeter. In any case I took the Acura mechanics advice and replaced the front bank No 1 O2 sensor. Reset the ECM and drove the car. Now the ECM stays in closed loop after warming up but does ocilate between closed and open-drive loop. Had the scanner logging the data on the run. Guess what, the original back firing and lean running condition is back! The car almost stalls when stepping on the accelerator even when the car is fully warmed up! After the engine reaches 3000 RPM the power returns and it drives with full power! What now mass air flow sensor? I just can't get a break with this car!
Codes now present:

Control Module
$10 ISO 9141-2
Stored Codes
P1201
P1202
P1203
P1300 Random Misfire Misfire

It if were me. I would use an ohm/volt meter and read the voltage directly at each of the O2 sensors and watch for erratic readings. You may need to use an analog volt meter as it may change too fast for some digital meters.
 

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If I'm not mistaken those are misfire codes for the rear cylinder bank. I had those too inclusive of the 1300 code. I was told it was a bad igniter, bad coils, etc. I took my injectors out, sent them to RC to be cleaned and blueprinted and problem gone.
 
Re: California Smog test failed now too lean!

The injectors were cleaned by RC and my coils have been individualy tested and installed by myself. The P codes are for rear bank cylinders 1, 2 and 3. This new lean condition has happened at least once before. Could be igniter? The last smog test it started out too lean (fail) then too rich (fail) all within 20 minutes. Some part is still not doing it's job, not sure what to do next. After the engine is hot and reaches 3000 RPM the power returns and it drives with full power above 3K rpm but almost stalls below 3K. This has happened twice after reseting ECM and driving the car so now this is a persistant problem instead of an intermittant one. It is depressing doing seven years work on my dream car and not being able to drive it :(


If I'm not mistaken those are misfire codes for the rear cylinder bank. I had those too inclusive of the 1300 code. I was told it was a bad igniter, bad coils, etc. I took my injectors out, sent them to RC to be cleaned and blueprinted and problem gone.
 
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My next problem after previously replacing three bad coils is a suspect igniter on lower bank. When the car is cold there are no issues but once warmed up (5 min on highway) No power and stalling and hesitation on acceleration until 4K rpm. Check engine light and traction control lamp comes on. Codes P1201, P1202, P1203 and P1300 Random Misfire Misfire. When cold problem goes away. The igniter is $500 or so new, decided to find a cheaper solution. Went to local pick a part Ecology Auto Recycling (Foreign yard in Otay Mesa, CA) and picked up two used OEM ones for $12. The Acura part is universal and used in 90% Acura 6 cylinder cars from 96 to 2005. found a 99 Acura TL and removed two to test out. Will get back with test results. I pluged in both 99 Acura TL igniters and the car imediately throws up ODB error P1316 "Spark Plug Voltage Detection Circuit Malfunction, Front Bank" Putting original igniters back, there are no codes until the car warms up. Well, I only wasted $12 (no returns). Aparently the other igniters do not put out enough voltage for the NSX coils. Back to the drawing board. Tried switching igniters and car would not start! put them back in their correct locations and insolated the rear bank ignighter with plastic spacers to remove from manifold heat. Same issues big delay on throttle when car is hot. Almost stalls under 3K rpm. New P codes though

Control Module
$10 ISO 9141-2
Stored Codes
P1318 Spark Plug Voltage Detection Module Reset Circuit Malfunction, Front Bank
P1319 Spark Plug Voltage Detection Module Reset Circuit Malfunction, Rear Bank
 

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I see that you have replaced the fuel pump. Is it OEM? Is it new?

Also, check the fuel pump resistor. Bypass it and drive. My car went like crap with the resistor connected to the harness and fired all sorts of codes, among these faulty O2-sensors. Problems went away when bypassing the resistor. Easy check.

Good luck!
 
I'll start off with "I am not an expert...!"

Through the log it appears fs1 and fs2 are always doing something diffident.
I don't think this is correct.

Short and long term fuel trims should total to less than 10 in closed loop.
Yours are whacked out. bank 1 is pulling tons of fuel out and bank 2 is adding fuel.

I would not bother to go in for a retest until this is fixed.
At idle they should be very close to zero. Once in closed loop. It Shouldn't take long to get into closed loop.

The only time I saw both banks in closed loop at idle is when the car was cold ????

DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 32.2
ETC(°F) 131
SHRTFT1(%) 1.6
LONGFT1(%) 0.0
SHRTFT2(%) -25.8
LONGFT2(%) 0.0
MAP(inHg) 9.5
RPM(/min) 997
VSS(mph) 0
SPARKADV(°) 28
IAT(°F) 108
TP(%) 9.4
O2S B1S12--B2S12--
O2B1S1(V) 0.000
SHRTFTB1S1(%) 8.6
O2B1S2(V) 1.275
SHRTFTB1S2(%) 9.4

After that bank 2 was always open loop. Whats up with that?

DTC_CNT 0
FUELSYS1 CL
FUELSYS2 OL

LOAD_PCT(%) 31.0
ETC(°F) 131
SHRTFT1(%) 19.5
LONGFT1(%) 0.0
SHRTFT2(%) 0.0
LONGFT2(%) 0.0
MAP(inHg) 9.2
RPM(/min) 1065
VSS(mph) 0
SPARKADV(°) 21
IAT(°F) 109
TP(%) 9.4


You are driving and in closed loop. bank 1 is pulling fuel out but bank 2 is adding fuel? WTF?


DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 63.5
ETC(°F) 183
SHRTFT1(%) -30.5
LONGFT1(%) 0.0
SHRTFT2(%) 43.0
LONGFT2(%) 0.0
MAP(inHg) 22.2
RPM(/min) 3016
VSS(mph) 71
SPARKADV(°) 25
IAT(°F) 106
TP(%) 27.1



As I recall your trims between the two banks should be almost exactly the same.
 
NSXNUT,

Thank you for the reply, many have viewed this thread but none have offered any opinion of my logged data. You are the first! I am going to bypass fuel pump resistor beacause I have an OEM manufacturer aftermarket pump. That should deal with the no power under 3K rpm but probably not affect the bizzare readings from the live data capture. My ECM computer was sent out to be checked. After I got it back they confessed that no parts were replaced, they did not have any software to program ECM and that it was tested in a Honda Civic! What a bunch of crap! I filed a claim with my bank for the three hundred dollars they charged me. This ECM is extremely rare an nobody has one to test in my car. Hate to buy a new one only to find that is not the problem. Have already purchased many un needed parts. Going to replace bank 2 primary O2 sensor like I did the front bank even though it was a new part with less than 200 miles on it and test again. The saga continues....

I'll start off with "I am not an expert...!"

Through the log it appears fs1 and fs2 are always doing something diffident.
I don't think this is correct.

Short and long term fuel trims should total to less than 10 in closed loop.
Yours are whacked out. bank 1 is pulling tons of fuel out and bank 2 is adding fuel.

I would not bother to go in for a retest until this is fixed.
At idle they should be very close to zero. Once in closed loop. It Shouldn't take long to get into closed loop.

The only time I saw both banks in closed loop at idle is when the car was cold ????

DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 32.2
ETC(°F) 131
SHRTFT1(%) 1.6
LONGFT1(%) 0.0
SHRTFT2(%) -25.8
LONGFT2(%) 0.0
MAP(inHg) 9.5
RPM(/min) 997
VSS(mph) 0
SPARKADV(°) 28
IAT(°F) 108
TP(%) 9.4
O2S B1S12--B2S12--
O2B1S1(V) 0.000
SHRTFTB1S1(%) 8.6
O2B1S2(V) 1.275
SHRTFTB1S2(%) 9.4

After that bank 2 was always open loop. Whats up with that?

DTC_CNT 0
FUELSYS1 CL
FUELSYS2 OL

LOAD_PCT(%) 31.0
ETC(°F) 131
SHRTFT1(%) 19.5
LONGFT1(%) 0.0
SHRTFT2(%) 0.0
LONGFT2(%) 0.0
MAP(inHg) 9.2
RPM(/min) 1065
VSS(mph) 0
SPARKADV(°) 21
IAT(°F) 109
TP(%) 9.4


You are driving and in closed loop. bank 1 is pulling fuel out but bank 2 is adding fuel? WTF?


DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 63.5
ETC(°F) 183
SHRTFT1(%) -30.5
LONGFT1(%) 0.0
SHRTFT2(%) 43.0
LONGFT2(%) 0.0
MAP(inHg) 22.2
RPM(/min) 3016
VSS(mph) 71
SPARKADV(°) 25
IAT(°F) 106
TP(%) 27.1



As I recall your trims between the two banks should be almost exactly the same.
 
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Today I installed new same type as front rear bank primary O2 sensor and bypassed the fuel pump resistor. Made a shorting plug from an unused horn that fit the resistor connector. Now the car runs great hot or cold with no CEL light coming on. Captured the test ride live data from the ECM. It seems to run better but reading scan results it shows improvement but not 100% stability. I see in closed loop leaning on the front bank and added fuel on the back bank on some capture entries. By the way, this car does have DC Sports headers. What else can I do, is this close enough?
 

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A while back I had someone swap out the injectors and they use the wrong impedance. The car ran like crap.
Diffident years need high or low impedance injectors. The fix for my car was to bypass the resistor.
You need to get this right. There is a resistor per injector.

My understanding is the secondary O2 sensor is only to test the cat.
Fuel is based on the primary sensor.

I heard some of the headers the o2 sensor is not in the right spot and makes it harder to pass smog.
I though it was the early Comptech not sure? I have Comptech headers and have had no issue with smog.

I drove my car the other day and hooked up my scanner. I have the scan gauge II My car is a 1995 and has OBDII.
I only have a single short term fuel trim Long term fuel trim and Loop, It doesn't split out the banks.
I have programmed it to look at all 4 o2 sensors.
O2 sensor reading should very. If they don't the sensor may be bad.
I had a marginal primary sensor at one time. Scanner helped debug.


Closed loop is Steady state. aka idle after warm up. Cruising at a constant throttle. Accelerating the car will go into open loop.
Ca Smog test the car should be in closed loop. You should be looking at steady state results.

On my car the scanner data is not Live data. The interface is to slow for this.

Looking at the data it seems to be better but I notice the Load varies significantly.

Drive the car like the smog tech would.

Warm up the car "coolent is 160F +" Let it idle and capture this.
Drive the car at 15mph constant throttle second gear for 1-2 min. Gently excel to 25mph third gear another 1-2 min constant throttle. Stop.

Look at your results. You need this to be perfect.
In you scan data you are driving at 75+ mph.

If you make the car run well in the test conditions I suspect it should run well most of the time.

Later,
Don
 
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Don,

Thanks for the help and advise. My injectors are the low impedance type and were restored by RC Engineering. Sounds like you are one of the lucky 95 NSX owners that got an ODB2 scanner connector. My car did not come with one and I had to wire one in myself! I'm using a Harbor Freight CENTECH 98614 Scanner(Relabled Autel Maxiscan). I think it's enough to point me in the right direction. It does not have Acura codes or diagnostic modules for everything like ABS, SRS, EPS, etc. but I would rather spend money on needed parts to get this car running than buy a capable several thousand dollar scanner that I won't need after this repair. The secondary O2 sensor is to record that there is a Cat installed and that it is functioning within range. It has no bearing on the mixture. I have an appointment today at 1:30 pm to do the smog pre scan again. Hopefully I will pass this time! After the car gets to 180 degrees the banks readings are farther apart and short FT adjustments become out of whack.

Here is a capture at idle at 120 degrees:
DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 34.5
ETC(°F) 120
SHRTFT1(%) -9.4
LONGFT1(%) 0.0
SHRTFT2(%) 4.7
LONGFT2(%) 0.0
MAP(inHg) 10.3
RPM(/min) 1065
VSS(mph) 0
SPARKADV(°) 30
IAT(°F) 77
TP(%) 9.8
O2S B1S12--B2S12--
O2B1S1(V) 0.840
SHRTFTB1S1(%)-16.4
O2B1S2(V) 0.800
SHRTFTB1S2(%)-17.2
O2B2S1(V) 0.020
SHRTFTB2S1(%) 13.3
O2B2S2(V) 1.275
SHRTFTB2S2(%) 0.8
OBD OBD2

Here is a capture at 32mph at 126 degrees:
DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 25.9
ETC(°F) 126
SHRTFT1(%) -10.9
LONGFT1(%) 0.0
SHRTFT2(%) 15.6
LONGFT2(%) 0.0
MAP(inHg) 5.3
RPM(/min) 2197
VSS(mph) 32
SPARKADV(°) 47
IAT(°F) 77
TP(%) 10.6
O2S B1S12--B2S12--
O2B1S1(V) 0.900
SHRTFTB1S1(%) 10.9
O2B1S2(V) 0.720
SHRTFTB1S2(%) 6.3
O2B2S1(V) 0.800
SHRTFTB2S1(%) 1.6
O2B2S2(V) 0.960
SHRTFTB2S2(%) 2.3
OBD OBD2


A while back I had someone swap out the injectors and they use the wrong impedance. The car ran like crap.
Diffident years need high or low impedance injectors. The fix for my car was to bypass the resistor.
You need to get this right. There is a resistor per injector.

My understanding is the secondary O2 sensor is only to test the cat.
Fuel is based on the primary sensor.

I heard some of the headers the o2 sensor is not in the right spot and makes it harder to pass smog.
I though it was the early Comptech not sure? I have Comptech headers and have had no issue with smog.

I drove my car the other day and hooked up my scanner. I have the scan gauge II My car is a 1995 and has OBDII.
I only have a single short term fuel trim Long term fuel trim and Loop, It doesn't split out the banks.
I have programmed it to look at all 4 o2 sensors.
O2 sensor reading should very. If they don't the sensor may be bad.
I had a marginal primary sensor at one time. Scanner helped debug.


Closed loop is Steady state. aka idle after warm up. Cruising at a constant throttle. Accelerating the car will go into open loop.
Ca Smog test the car should be in closed loop. You should be looking at steady state results.

On my car the scanner data is not Live data. The interface is to slow for this.

Looking at the data it seems to be better but I notice the Load varies significantly.

Drive the car like the smog tech would.

Warm up the car "coolent is 160F +" Let it idle and capture this.
Drive the car at 15mph constant throttle second gear for 1-2 min. Gently excel to 25mph third gear another 1-2 min constant throttle. Stop.

Look at your results. You need this to be perfect.
In you scan data you are driving at 75+ mph.

If you make the car run well in the test conditions I suspect it should run well most of the time.

Later,
Don
 
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Did smog test today, as usual I failed again. There also is this wicked delay between pressing the throttle and the car accelerating, a full two seconds. Is this normal for 95 era NSX cars? My 2006 Toyota has throttle by wire and I don't see this problem with it, Back to the drawing board.

Test date 10/08/11
Test _______ Rpm |%CO2|%O2| HC (PPM) ______ | CO(%)
_M1: 15 mph 2470 | 9.9 | 3.6 | MAX 85 Meas 388 | MAX 0.50 Meas 4.64|
_M2: 25 mph 2427 | 10.0 | 3.4 | MAX 50 Meas 330 | MAX 0.47 Meas 4.64|
 
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