Background information:
I had a failed airpump and so I took my car to a shop to get it installed (simple job). While I was there I had them run a pretest on my car. Below are the results:



It passed emissions but failed the CEL/MIL test (powerFC).

So then I took my car to a test only station (required) that I know will let the CEL/MIL slide as long as my emissions are fine. Despite the great pretest results, the second guy ran a complete different set of numbers.



Kinda hard to see--
15 MPH: co2=14.2, o2=.2, hc=82, co=.74(fail--.52 max), no=66
25 MPH: co2=14.2, o2=.1, hc=77, co=.72(fail--.50 max), no=68

Both times, the car were on rollers and both times the sniffer was all the way inside the tailpipe. Anyone know what's goin on?

 

Was your cat fully warmed up the second time (> 30 minutes of highway driving)?

 

Well my car idled about a good hour I'd say at the first place. The guy had trouble finding my RPM. I left the first shop and basically drove it to the second shop. It sat parked for about 15 minutes in the sun and then he let it warm up about another 15 minutes (idle).

I checked the temp on my powerFC and it was 94C before he began the measurement

 

Your O2 numbers are significantly lower in the second test - are you sure your air pump was working?

 

Yes, I bought a used one off a forum member and I had the first guy put it in for me. When driving around I can hear it kick in around 2600 RPM. What I was thinking was maybe the first guy kept the RPM around where the airpump would kick in.

I dont know what gear the first guy used..second guy used second gear for 15mph (failed) then tried third gear for 25mph but still failed

 

The PFC turns off the air pump at 2500rpm (it is on from 0-2500rpm; the stock ECU turns it off at 3000rpm).

I can't read the rpm numbers on the second test but I think they were both under 2500rpm, which means the pump should have been on.

 

1804 RPM for both 15 and 25 MPH on the second test

 

Is it me or I am having a very hard time reading the "failed" smog result.

I would like to read the numbers in order to help diagnose your problem.

-AzEKnightz

 

I am stupid, I didnt read thru the post. Forgive me.

From the readings you given, you vehicle is running a tad rich. Heres a trick many "smog" tech do on their cars if it fails not by much.

1st, seafoam or fuel inject clean the vehicle. Make sure it's clean.

2nd, before u redo ur test, fill it up with premium, and goto safeway or something and buy urself a bottle of rubbing alcohol and pour it in the tank.

3rd, like someone mentioned earlier, drive ur car HOT, when u want to take the test, may I ask if you have your pre-cat taken apart and replaced with a dp? If so that's where I would guess where you failed at.

Also, make sure your injectors aren't leaky.
Intakes arent restricted.

Hope this helps a little bit. Let us know.

-AzEKnightz

 

More recent gasoline formulations in the US now have 10% ethanol so a bottle of ethanol from Safeways will not do much. (And rubbing alcohol is not what you want to use in any case - it may not contain any ethanol.)

Also, a pre-cat is absolutely not required to pass a California emissions test.

Seafoam won't hurt; neither would new plugs.

 

I passed with a DP and new plugs.

 

I've passed before with a downpipe and currently using an HKS dp. Injectors have been cleaned and balanced not so long ago. Plugs are relatively new as well. Perhaps I'll check out the seafoam thing--although I'm always a bit wary when it comes to fuel additives.

 

I dont really want to be a dick or what so ever. I can 100% guarantee you, IT IS LEGIT to have a pre-cat to pass. The reason WHY so many people has passed with a dp is, 1st, the smog tech is lazy to look for the pre-cat.
2nd, NOT all techs know where the pre-cat is located in an FD.
If you dont believe me, go check the "bible" for smog techs, it clearly stated that it REQUIRES 2 cats (A Pre-cat and a Cat) to actually pass the "visual".

And why I said rubbing alcohol, i dont mean regular ones. It must be the 95% rubbing alcohol. (I guess this wont do much like you said, but it worked on alot of the cars I've recommended)

Why I am saying this? I am a certified Smog tech (I can fix failed smog cars and I can smog a regular or dirty *** smog vehicle)

I am sure you are one of the knowledgeable personel on the forum. And I respect that. But what I am saying is 100% legit, this is from learning thru experiences and knowledge passed down by my instructor.

Hope this actually clarifies my posts.

P.S. The alcohol I refer is used to clean out the injector what not, but use with SeaFoam does work.

Give it a shot.

AzEKnightz

 

I should have been more clear - I was referring to the sniffer part of the test. You are right - a downpipe is definitely not CARB legal (though fortunately most smog techs don't bother looking for it).

 

The only difference I noticed, is that in the first test the 02 reading was .49 and .61, and thats why you passed. I cannot read the second result, but according to what you wrote down, the air pump reading was only .1 and .2 which means it isnt doing anything. I would pop the hood and check "visually" to see if its clutch is spinning, and functioning properly, I believe this is your problem. Testing the air pump is fairly simple and doesnt require taking anything apart, just look in the FSM "Fuel and Emissions" section and it will tell you how it supposed to work

Also, make SURE you check on both tests to see if the RPM's were the same, or different. Example: my first test (with a NON-working air pump) @ 25mph was a 2900rpm and I almost passed. My second test(with a WORKING air pump) @25mph was at 2000 rpm and I failed? here my results, maby this will help you out.

 

I have no doubt you are speaking from experience. However, I have passed several smog tests in california (Los Angeles) without a pre-cat. I think it's fair to say that most technicians, regardless of their reference material, are naive when it comes to RX-7s. I.e. I'm not so sure that any given smog tech knows there are supposed to be two cats on an FD.