Emission testing : Failed, NOX and CO2 out of range..?

[samiam44]

Ok,

I thought things would be easy this year- heck I finally put the correct plugs,1 new cap/rotor, fresh air filter, 02 sensor in the car. It's running much better, but it seemed to be getting lower fuel miles before the reserve light came on. Just blamed it on Ethonol and my wife's car I rarely drive much.

So, they couldn't get a good reading.. emissions testing timed out.

I can do just about anything.. but don't know where to start. My though it replace low hanging fruit- maybe the original airpump check valves.

If there was a problem with the 02 sensor- I'd get a CEL correct?


Michael

 

[gerryvz]

The air pump only works for the first minute or so after starting a cold engine. It won't have any affect after 60-70 seconds....

 

[edcarls]

So, they couldn't get a good reading.. emissions testing timed out.

What was the NOX and CO2 reading? I mean how much are they off?

Here in CA if it failed emission test the print out would indicate where it failed and by how much. These information would provide you some hints on what corrective action may be needed.

 

[gerryvz]

It doesn't sound like they could get a reading. I'd take the car to another tester. Did they do a dyno test or an old-fashioned static test? Here locally in Houston they won't do dyno tests with my ASR cars (E320 wagon and E500).

 

[samiam44]

Static test...


It's a non-asr car. Weird, it passed before at this same shop the last 2 years. They couldn't get a reading... Does using the dyno help- they have one in that bay.

Filled up the tank with a some techron.. and well run it through, change the oil etc.



Michael

 

[gsxr]

If they can't get ANY reading... it's a problem with the emissions station test equipment (or technician), not your car.

 

[samiam44]

OK here's the results. Note the 25mph and 15 mph results are nearly identical as it was done on the dyno and not just with the RPM. I took it to a different place. Put it fails miserably. Maybe I should cough up and work on the airpump/check valves(C&D rebuilt) and replace the 02 sensor with the proper one from authausaz.

HC 288 (108 allowed)
CO 5.44(0.60)
C02 11.2
02 0.3
NOX 287 (751 allowed).

Dillution is 16.6 %

They were so polite selling services. Yea.. our mechanics can pull the codes(yea right) and we can fix it. Thanks, but no thanks.

 

[DerFuror]

HC 288 (108 allowed)
CO 5.44(0.60)
C02 11.2
02 0.3
NOX 287 (751 allowed).
Dillution is 16.6 %

The hydrocarbon emission reading is high which would indicate incomplete combustion (raw fuel gas passing thru the exhaust system). The high CO reading further complements this indication.


Since you have replaced the plugs & several key ignition components, verify the condition of the plug wires. The signal to at least one of the cylinders may be intermittently impeded.

To do so, first check each plug for fouling. If it's one plug, check its wire continuity while wiggling it around. Hopefully that's it; replace wire. If all plugs appear somewhat fouled (darker/sootier than expected), then the items providing sourcedata to the computer should be further investigated.

...also consider the possibility of a fuel injector misfiring if plugs & wires are ok.

 

[gsxr]

I'm also suspecting the catalysts might not be working properly. I tried to get my car to pass smog like that, didn't work:

No cats:
Idle = 320 HC, 1.12% CO... 2500rpm = 205 HC, 1.06% CO.

Cats installed:
Idle = 36 HC, 0.05% CO (2500rpm test not required since it passed idle test)

What is the age of the O2 sensor? Age of the MAF (if known)? Stock LH? Stock chip?

 

[gerryvz]

+1 on the cats. Replace 02 sensor while you're at it.

 

[samiam44]

Well.. this car didn't have any problems last year and we're only 4-5,000 miles different.

I'll check plugs and wires. It doesn't seem to miss noticeably. But I will verify. I had only put in 1 cap and rotor which were in bad shape... maybe go back and do the other side.




Michael

 

[gsxr]

Just FYI, O2 sensor info is detailed in this thread:
http://www.500eboard.com/forums/showthread.php?824-Oxygen-sensor-information&

 

[samiam44]

How about just a little age related drift on a temp sensor causing it to always run slightly rich?

I replaced one on my 300e and it went from barely in range to very low emissions the following year.


Michael

 

[gerryvz]

d00d, you have to attack the problem logically, methodically and from a position of having accurate data, rather than guesswork that it could be a temp sensor or a smog pump (which plays no role in emissions other than for the first 60 seconds or so after a cold engine is started). First off you need to pull codes from the car to see what you're dealing with. Clear the codes that are there, and run the car for a couple hundred miles to pull 'em again and see what comes back.

Then you really need to get the opinion of an expert (i.e. indy shop) on this and have them diagnose the problem and get it solved. Like we've said, you've got to look at the effectiveness of your catalytic converters and the feedback look to the LH computer (i.e. O2 sensor). Did you pull codes? If not, why not?

 

[samiam44]

Re: Emission testing : Failed, CO and CO2 out of range..?

Thanks Gerry!

I'll pull and clear codes today. Measure temp sensor,check wires, check 02 sensor etc.
Monday I had planned on making an appointment with an Indie.


Michael

 

[samiam44]

think the NOX is within it's bounds and passed. So, CO and CO2 are the problems. I'm pulling codes and got PIN 4 (22 and 23) which are 02 Sensor 1 heater, oen/short circuit. 23= purge control valve, open/short circuit.

OK- 02 sensors. The bosch ones have a horribly long lead- do you put those in and wire-tie the excess together or order a factory sensor? How about using the aftermarket bosch for a 92'? That has a shorter lead.

PIN 6 car has only ABS(no traction control)

13, 25 , 26,... sounds like I've got a bad ABS unit or computer.

PIN 7 (cruise, idle)
2 - seems to be anything !! safety switch, control module , stop switch etc
6 - starter lock-out /back up lamp switch
11 - Closed throtatl signal, fuel safety shut-off to engine control module right or left side (LH-SFI)

Pin 8 code 5.. max temperature in module exceeded

PIN 19 DM, (3, 12, 25).
3= Lambda control faulty
12= HEated 02 sensor faulty
25= knock sensors or engine control module faulty.


How do I set the computer into new adaptation mode after I put a new 02 sensor in the car??? ABS stuff is worry some. It acts really weird at low speeds sometimes.. like you have no brakes.

Michael

 

[gsxr]

Your spliced-in sensor isn't working right... that's why you're getting the error codes for the oxygen sensor. Replace it with one of the aftermarket Bosch, I'm using the 1992 style in all my cars, but you could tie-wrap the longer wire, or just shell out for the OE sensor from parts.com.

For all the other codes, just clear them and see which (if any) return quickly. If your starter lockout / neutral safety switch is original or at least not recent, it may need replacement, based on cruise/idle codes 2 & 6 (pretty common).

To reset the adapation after installing a new O2 sensor, clear all codes on pin 4 (LH), then try to "clear" the single blink as if it were an error. This resets the module. It's all in the documentation. Click here, see page 6, right side of page, under the heading "Resetting LH-SFI Control Module's Self-Adaptation Feature to Mean Value".

 

[samiam44]

snip from Jono

"If CO and CO2 are the problem, yes..lets start w/ a Real O2 sensor.

Has the ETA on this car ever been tended to? You are getting some of the errors i see that are consistant w/ ETA problems.. Have you cleared all the codes and this is what came back?

Both knock sensors being bad in unlikely..but you might want to inspect the wiring. If the EZL is constantly pulling timing that would lead to issues as well.

I usually just tie up the extra lead...better to much etc..

Your purge valve should start to click @ random intervals, more so w/ car cold..check it out...JIC< it's the one that says MOT on it on the drivers fender well

jono"​

Michael

 

[samiam44]

I've been busy so an update!

The new 02 sensor is in the car, re-set the computer, added dry gas. Seems better but I didn't check/reset pin 17(ezl) until Dave mentioned it. So, I'll drive it some more tomorrow and check again. It's in adaptation mode- so maybe get a full tank of fuel on it before taking it for re-inspection.

The purge valve doesn't make a noise. It appears to be failed in the open position, so I have plugged it as a stop gap measure.

I measured both the abs sensors- and the wiring looks good. The resistance is 1.5, and 1.8 k ohms.

The stored code in the ezl (pin 17) was 18. "Magnets for CKP sensor not recognized (diagnostic trouble code 18)" What the heck? Is that saying the flywheel magnet is missing?

Michael

 

[gsxr]

Yeah, code 18 on the EZL means the flywheel sensor isn't recognizing the magnet(s). The engine won't start or run if it doesn't sense them at all, so this would be a very intermittent problem. If the code comes back rarely, it could be a sensor issue - my '92 wouldn't always fire on the first try, and had a code 18... adding a 0.5mm shim under the sensor per this TSB cured it. On my '94 the problem was more frequent, and code would appear EVERY time the car was started. That turned out to be one (of the two) flywheel magnets missing - details here. I wouldn't worry about it unless you have starting issues, and/or the code keeps coming back.

 

[samiam44]

Here we go again.. Today it's 55F, and the car sat a long time before testing.

Here's the results , HIgh speed emission (25mph)

RPM 1351
HC 261 (max 108)
CO 0.36 (max 0.6) was huge before(5?)
CO2 14.6
02 0.5
NOX 898 (751 max)


So, CO passed this time where now HC and NOX failed. Maybe the cat wasn't hot enough?


15mph test
RPM 1372
HC 317 (112 max)
CO 0.64 (0.6 max)
Co2 14.1
O2 0.8
NOX 1765 (max 829)


FIXED FIXED FIXED. Note to anyone- get your inspection done in August!! Then it's warm. The inspection guy put the heater on and tested the car(it's 50F and raining today!). It failed barely and he imediately went through the cycle a second time. Passed... WHEW till august.