Just passed CA smog

[barrbm]

Hi all:

I just took the car in-- 2002 Miata SE with FFS coldside-- for a smog check and passed with flying colors! The technician did call in to check the validity of the EO, which apparently went fine.

Thanks, Tom and Bill, for all the help and advice during the install. I think the car is running very nicely.

I also took it in for an oil change this morning, and the system garnered quite a bit of attention from the mechanics.

Great system!

b

[Tom @ Fast Forward]

Way to go. I love it when a plan comes together.

[Rdrcr]

Yep, mine passed to, no problems whatsoever!

Great kit and excellent support.

Mike

[Tom @ Fast Forward]

To the best of my knowledge, of the 35 or so kits in CA, the batting average is 100. I have not heard of any NOT passing.

[socal pat]

Exactly. If your car will pass without the kit, it WILL pass with it. Heck, with the many intake manifold issues on the 99-00 that we hear about with blocked passages it might pass more easily with the new manifold.

[jwalton]

Mine passed with flying colors about two months ago. The tech really liked the installation of the kit. Enough to take the time to tell me. Tom does good work and o mostly follow instructions.

[Digitac]

Well, I hate to break your perfect record Tom, but my mean-green-ping-monster won't pass. I've been fighting this damned thing for 3 years and it's always got 10x normal NOX levels. I've gotten THIS close to either parting the whole thing out or smashing it with a sledge hammer. No one can figure it out.

--Digitac

[socal pat]

One thing to try.... put 3 gallons of E85 in with a tank of normal. This will lower the NOX (by how much I can't say for sure) but it will lower that number.

[FormerDatsun510Man]

If you have 10x the normal level of NOx it sounds like an emissions control part that is simply not functioning. The engine or fuel on its own would not make that sort of difference, provided it has a stoich air/fuel mixture and your ignition system is up to snuff. Off the top of my head, EGR. The EGR is primarily for reducing of NOx gases. It is possible you have no codes but the EGR is not functioning. There are three main components to the EGR system. You have the EGR valve itself which is located on the intake manifold (with the short little stainless pipe supplied with the FFS kit), Boost Sensor and the EGR solenoid valve (both of these located next to each other on the passenger side of the engine bay. In my case, I had a failed EGR solenoid valve. Replaced with a used one for $10, problem solved! Actually, I swapped out the other two but found out from trial and error that the only problem had been that darn solenoid valve. I had an error code (forgot which one now sorry), but it is possible to have an issue and no code. For example, if the pipe is blocked off at the exhaust manifold and you have fresh outside air going into the EGR valve, you can get away with no codes, but essentially a non-functioning EGR. Btw, I have come to really like the EGR. Why? For some reason, when I had a non-functioning EGR on E85 I was getting only 22-23mpg on my drive to and from work. With it working now, I am getting closer to the usual 25mpg (on E85). Lower emissions and better mpg, what is not to like? :)

Well, anyway, EGR is just one of many possibilities that comes to mind. Another possibility would be if your CAT got hosed for some reason. Most likely reason on a Miata is a coilpack failure, which can be intermittent.

[Digitac]

Thanks for the advice, but I've got a small collection of replaced EGR valves, Cats, O2 sensors, Coil Packs, spark plugs and other parts that I've replaced numerous times. Though I don't think I've replaced the boost sensor.... hmmm. Maybe I'll try that next.

[Tom @ Fast Forward]

I know its a long drive but the offer still stands. Drive down and stay at our home. Lots of room and we will make it right for you. instead of trial by replacement, Curt can actually test and diagnose and repair. We have the equipment to monitor NOx.

[Tom @ Fast Forward]

I've probably asked this a dozen times but what is your long term fuel trim?

[Digitac]

I may just have to take you up on that Tom.
I'm not sure what my LTFT is when driving, but I just checked it in the driveway and it was between -8 and 0 at idle and 1500 RPM respectively.

Jonathan

[Tom @ Fast Forward]

Just let it sit and idle a few minutes and let me know what happens to LTFT and ATTRACT.

[Digitac]

So I finally got a chance to work on the car again. I tested the EGR Solenoid valve by putting +12 across the connector and it seems to be fine. I replaced the EGR Boost sensor and had it tested again. The numbers dropped significantly, NOx is now in the 1400 range rather than the 2700 range, but it's still 3x acceptable limits.
I'm not sure what ATTRACT is Tom, but I set up my ScanGauge to watch LTFT1 and I saw numbers from -18 to +18. At idle it seems to be around -8 until the radiator fan kicks in and it drops with the engine temp to -14 or so (spiked to -18). When driving it was usually around +13, with spikes as high as +18 under light acceleration.

I'm not sure if that info is useful, but unless someone has another idea I might have to sneak the car out to AZ to take Tom up on his offer.

Digitac

[Tom @ Fast Forward]

Monitor the LTFT at idle (currently -14) and clamp the fuel line to the extra injectors. See if that number changes.

"-" numbers means the engine is too rich and the ECU pulls fuel from the main injectors to correct. "+" numbers means that the engine is lean and the ECU adds fuel to correct.

LTFT souldn't move around that fast. STFT does but LTFT should be the average of "long Term".

Remember too, at idle the engine uses so little fuel that an insignificant change could be a large percent.

Maybe it just needs a few drive cycles to get back in control of the EGR? This is a list of high NOx causes. http://www.ehow.com/list_7619425_causes-high-nox-emissions.html

Oops. I forgot to add, you are welcome anytime. Our home is always open to family and you are all family.