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-   -   Almost got my FD passing CA smog. Need help on final items. (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/almost-got-my-fd-passing-ca-smog-need-help-final-items-947823/)

mdpalmer 04-01-11 10:26 AM

1 Attachment(s)

Originally Posted by mdpalmer (Post 10547082)
Can you scan a copy of the dyno test results? Would help to narrow down the problem. I went thru this almost 2 years ago. I passed with a Power FC, 20+k mile street port rebuilt motor (used housings, irons, etc.), stock cat, NO precat, non-seq twins, 3" M2 exhaust, stock mount IC, 91 oct, supra fuel pump, 1300 cc secondary injectors, m2 airbox, 7 leading, 9 trailing plugs, fresh oil, PCV valve intact, purge control intact, ACV new gaskets, ACV plumbing and solenoids verified to work (at room temperature), air pump working and plumbed, check valve @ air pump was fine, blah blah. I leaned out the fuel on the PFC to about 15-16:1 and my CO was literally 0. NOx was pretty high however. HC was well below limit.

If your air/fuel ratios are off of stoich (14.7:1) it will affect your results quite a bit. See chart below. Do you have a wideband on your car?

http://www.stealth316.com/images/fic-af-emissions.gif

huh, the pic does't come out in my browser. i attached it here.

https://www.rx7club.com/attachment.p...1&d=1301671571

santacrs 04-06-11 10:45 PM

It seems the is too much fuel being pumped in. Stanley is checking out the air control valve to see if it isn't working properly. The car has been running very rich over the last few years and carbon build up could be causing the valve to not function properly. Unfortunately, it means removing the manifold to get it to it but its our best bet right now.

Stanley should be posting the smog result hopefully sometime this week but he's a bit bogged down with work right now.

If it comes down to it, we may try the denatured alcohol trick but I'm skeptic on it working and what damage it could cause. But also I kind of just want to figure this one out after the money I've put into it.

I appreciate everyone's input and help.

jeff p 04-07-11 07:31 PM

take the cats off and steam clean the engine to remove carbon in the motor. put the cats back on and change the oil. drive the car , get it hot and take it for smog. while your waiting for the test let the car idle dont lt cool down you should pass. !

i am no expert but this should lower you enough to pass the test!

Jeff

jeff p 04-07-11 07:33 PM

adding the HKS ignition with stock 7 & 9 plugs seems to help me pass smog! just a thought hope it helps... good luck!

Jeff

santacrs 06-21-11 11:58 PM

still ongoing
 
The latest reading from most recent repairs are:
HC 129ppm limit is 61 for 15mph 37 for 25mph,
CO 0.18% limit is 0.36% for 15mph 0.35 for 25mph,
NOX 0 and limit is 102 for 15mph 239 for 25mph

So my problem right now is the HC only. The CO & NOX are good to go.

Does anyone know if I try the ethanol e85 would work or where to even find it? does the ECU need any changes for e85?

Does anyone have any thoughts on what repairs I should look at to help with the above HC numbers?

Any help in removing this ongoing nightmare from my life would be great. I miss driving my FD. :(

Thanks guys.

Narfle 06-22-11 10:19 AM

Try the e85. It should bing your HC's down.

Typically you would need to tune for this, but in this situation just try to put a couple gallons in to complete the test. Then fill your tank and take it easy until you can further dilute the fuel mixture with gasoline.

wstrohm 06-22-11 12:27 PM


I would attribute passing to all the new gear (wires, plugs, cat) and maybe the cleaning of the EGR, though I'm told you should be able to pass with it removed completely.
The 2010 results for our '94 are posted here, FYI. All mods are shown in my signature, car is stock otherwise; cat is a Mazda OEM. Note that the EGR system is deleted. Original engine, 101861 miles, about 30K miles on the (replaced) Mazda cat. The test was done at a test-only smog station in Huntington Beach, CA.

IMHO the only way to go with a CA FD is with an OEM cat. Tried a new Bonez hi-flow, and failed. Looks like the Mazda cat has a better internal air distribution than some aftermarket types. The injected air has to get to all the gases flowing through in order to burn all the HC.

pomanferrari 06-22-11 10:54 PM

If denatured alcohol = isopropyl alcohol then don't waste your money - don't ask me how I know. You have to run methanol 1 gallon to 5 ratio.


Originally Posted by Karack (Post 10542922)
worse comes to worse, add in about 1 gallon of denatured alcohol($15 per gallon at home depot or any hardware store) per 5 gallons in the fuel tank then run the test, be sure to top off the tank after you finish the test.


santacrs 08-26-11 01:05 AM

Thanks for everyone help but we figured out the problem. The Air Control valve was the culprit. It had some blockage due to air pump not being connected properly and so the valve wasn't closing properly. Unfortunately Pro Inspections had to open the manifold to figure that out but mad props for doing so. Stanley at Pro Inspections knows his stuff. If your in the bay area I highly recommend him.


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