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Smog test woes, advice welcome

3K views 24 replies 16 participants last post by  Fritha78 
#1 ·
I have an indy that I really like, but he's methodical and slow, in the interest, usually, of economics. Took my sl600 in for state inspection and emissions test. Five weeks later, he's been unable to get it into a "ready" state for the test. He says that usually its a matter of a certain number of drive cycles, and he's seen one or two other occasions where it took a few hundred miles to get it to reset. He doesn't believe its a mechanical or hardware issue, just an electronic glitch.

Car is an LA car that came with current Cali registration. Owned by a doc and not driven much. No CEL. My s/o thinks I should just fire the wrench and move on. Not a large selection of good indy's hereabouts.

What say you guys?
 
#22 ·
96 sl500 OBD



Hey, glad to see your post with magic.
Did you have problem like mine to pass the smog test? OBD not getting ready after numerous Drive Cycle and repair shops all telling me nothing wrong enough to replace. I just had all the O2 sensors but still cannot connect to OBD. Can you possibly ask your mechanic at Sacramento of possible solution?
 
#6 ·
I just had mine smogged yesterday. 2weeks prior I had a CEL leading to an error in the EGR and MAP. Both have been addressed and the CEL lamp switched off after driving the car about 30minutes. Yesterday the errors still show on the OBD reader and was told that typically once I drive the car for about 60 drive cycles the history will drop off.

Long story short, its not an issue and I passed. Yours should too
 
#7 ·
Ok, it may be the 60 drive cycles thing. The issue is not that the tailpipe doesn't pass clean, the issue is that the OBD doesn't register "ready" for the test. The wrench is a good guy and very competent, but he'll chase a problem for a long time while keeping his customers who have only one vehicle on the road. I probably need to go pick the car up and drive the snot out of it for a week?
 
#9 · (Edited)
As far as I know, monitor "ready" state has more to do with whether the car was properly warmed up prior to the smog test, not number of drive cycles. Are you saying your mechanic has had the car for 5 weeks now?

Its definitely time to move on.

Also, if you have the results of your last smog test, some of the readings can help indicate what the problem might be.
 
#11 ·
Recent AZ test results on my 94 SL320 - HC in PPM: allowed 220, actual 3. CO in %: allowed 1.2%, actual 0%. Just ridiculously clean. I've had trouble passing with 119 motors in the past but always just added a can of "Guaranteed to Pass", followed the instructions, changed the spark plugs, and passed. Sounds silly but it worked so I stuck with it.
 
#12 ·
I don't know if the original poster is from California but I've never heard of a smog test facility turning away a car because it wasn't "in a ready state"

If this is it able to be reset by their diagnostic machine's and that's what they do.

When I originally read this I was wondering if he is from California because you start paying penalties if you have not smogged it successfully by the time the registration is due.

And keeping a car five weeks trying to figure it out borders on the ridiculous.
 
#13 ·
I don't know if the original poster is from California but I've never heard of a smog test facility turning away a car because it wasn't "in a ready state"...
In my experience here in Corona, CA, during the pre-test, "System not Ready" was reported by the scanner. The technician didn't not proceed with the actual Smog test. He said, if he perform an the actual test, it will result in failed smog test. He told me to drive the car until the "system not ready" message goes away. In my case, I drove around running errands about 20 mile for an hour. When I returned to the smog station it was ready.
 
#14 ·
Here in AZ for any '96 and newer car they have a special lane. All they to is plug in the OBDII wait for the computer read-out and your done, no rollers or engine run-ups, nothing and you're good for two years.

For diesels on the other hand they're absolutely barbaric. Every year I have to take my Dodge 1 ton Cummins diesel in and they have you floor the accelerator to check the governor and release to see if it returns to idle, while your doing this they have their machine sucking your tailpipe checking the exhaust for opacity. This stupid no-load rev to redline has to be done three consecutive times in order to pass.
 
#15 ·
Here in AZ for any '96 and newer car they have a special lane. All they to is plug in the OBDII wait for the computer read-out and your done, no rollers or engine run-ups, nothing and you're good for two years...
Same here in CA. The technician explained that the new Smog Testing System is more reliant on the car's computer system. Whereas, for old cars the Smog System computer it self does the testing.
 
#17 ·
My experience in NJ - I had a OBDII car that was tuned to turn off the rear O2 sensors - when getting the emissions tested, the car would fail because when 'pinged' the O2 sensors were 'Not Ready' - IIRC, you are allowed 1 sensor "not Ready' here and zero CELs - automatic fail.

So I went around the block, reloaded the stock tune, and took the car back and it passed. Pulled out of the lane and put the performance tune back in the parking lot.

Think of 'Not Ready' as a sensor not answering when the test calls it.

So when I had my next OBDII car tuned, the O2 sensors were off but they sent back a dummy signal of "Ready" whenever pinged. Car passed every time without drama.
 
#21 ·
Wow, It is not only my car with this problem.
I see everyone got lucky being able to resolve. My case of 96 SL500, I drove about 250 miles since Failed on OBD not Ready while emission passed. And went thru Drive Cycle few times. It wasn't simple nor easy at all. Still not READY.
I need to find what exactly cause this problem, planning to keep this car another 5 years.
Is there anyway to pinpoint out what is stopping to communicating with OBD II?
 
#25 ·
Have you considered contacting your State Senator? I know our situations are entirely different but I had a problem getting my car emissions inspected shortly after I got it. The inspection stations all wanted to put it on a 2 wheel dyno and the traction control would kick in and keep the car from getting up to speed. The first time it was inspected I thought they would wear my brakes out. I was told not to bring my car back to them. I tried contacting, via email, the State agency that is in charge of inspections. I was ignored. I finally emailed my State Senator about 4:30 one afternoon. At 8:30 the next morning I got a call from his office asking for details. The proper person was contacted by his office, I got an apology from the inspection office that had ignored me and was put in contact with a local supervisor that would take care of any problems in the future. My car passes with flying colors by the way, but must be checked via a 2 speed idle method instead of the dyno. I also received the necessary documentation which I take each year to show the inspector how it should be done. I did send the State Senator a $500 campaign contribution after all this was finished. Having this taken care of so quickly was worth it to me. I haven't had any problems since.

If all the people in California would contact their Senator each time they had this problem perhaps you might get this fixed. Perhaps not.

Doug
 
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