Hey guys,

Been away for quite a while, been focusing on other hobbies, etc. But the FD is doing great! After years of happy rotoring, this past year I got a new cat, an oil metering pump replaced, and a tune job on my Power FC (always ment to get it done) over at Rotary Power. All discovered due to a failed "pre-test". Jeff is amazing over there.

My current issue is as follows. I have a Power FC as I've just mentioned. It was dropped in in the early 2000's. This has historically makes for a difficult time smogging for many people. In the past I have passed fine, but the cars getting older, and following my recent complications (new cat, and oil metering pump replacement) I'm kinda apprehensive about getting it smogged. I had to replace the cat and oil metering pump last year because a smog "pre-test" showed I had some issues, and replacing these was the cure. Indeed last year after these fixes, it passed fine when mechanic took it to test. But I am not my mechanic. He mentions theres a bit of a trick to passing a smog test with my generation of power FC..something about shifting one more time durring the process...something about a difference between the Apexi unit, and the stock computer in regards to when it turns on the O2 sensor..or doesn't.

So..

Anyone have a Power FC? Are you passing smog with no issues? Is there something magical (like an extra shift to keep rpms down) that you need to do to pass smog? Admittedly I haven't tried to smog it yet..I guess I'm affriad of it being labeled a gross polluter, failing, and then having to smog it EVERY year..or worse..find a shop up here in the SF Bay area who can help me if indeed i do fail. The car is barely modded..just a powerFC + Commander Unit, Downpipe in place of the old evil pre-cat, Racing Beat intake, and an N1dual catback.

All Advice/Insight into any of this is welcome, and encouraged.

Thanks!

-jasonic

 

No advice on this? Any people with PowerFC smog issues, etc? If not, how do you pass every year? I can't put my stock ECU back in..the car freaks out and sputters like crazy.

What would you do if you were in my situation?

-j

 

First thing I would do is talk to your tuner/engine builder and see what they say. Otherwise, have a search in the power FC forum. There is lots of good information there. In any case, you need

1. Good, working cat (sounds like you're OK there)
2. Working air injection to the the cat (otherwise you'll likely be off the charts on HC and CO)
3. Fresh oil, fuel, stock plugs (if you're running "all 9's" like many of us, change the leading ones out to 7's which is a hotter burning plug)
4. Modification to make you're check engine light come on when the car is started (see Power FC forum, there are several ways to do this, otherwise you will not pass visual... there's a checkbox for the smog guy to check: "System Malfunction Light")
5. Working O2 sensor (if you're running O2 feedback on the PFC)
6. May have to temporarily cap off fuel vapor purge (canister under the throttle body) just to be on the safe side
7. Make sure car is 100% warmed up so the cat can do its job. Leave your car running before they put it on rollers.

You may have to tweak the fueling on the commander, but if you don't have a wideband on the car or datalogging, you're kind of shooting in the dark on that one... If you're running O2 feedback and your car seems to run OK I would tend to think you'd not have to change the fueling too much if at all... BUT if you have O2 feedback off you may have to tweak the fuel. As long as you can keep AFRs near the stoich point of gasoline (14.7:1) you will be able to maximize the cat's efficiency.

Check out the magnaflow website there is some useful info there on cats, efficiency, etc.

converter basics
efficiency charts
converter failures

Oh the other thing is that the tailpipe test is run at two speeds, 15 mph and 25 mph. I'm pretty sure they run it in 2nd for low speed and 3rd for high speed (last time I looked the rpms were 1710/1950 for 15/25 mph).... so you wouldn't have to modify a large portion of the fuel map...

 

The trick your mechanic was referring to was running the 25 mph test in 3rd gear and the 15 mph test in second. The goal is to keep the engine speed under 2500 rpm because the PFC shuts off the smog pump at that point and without it you're hosed.

 

I spoke to someone about Power FC awhile back. it will sure fail smog in CA. however if you keep the stock ECU, swap it back to pass smog then put on Power FC again.

 

Not true, I've passed smog with one. Keep it under 2500 rpm and do the CEL wiring modification and it should pass if you have a decent tune.

 

Excellent info!
Thanks very much guys

Maximum,

Can you explain the CEL modification? My wifes an Auto Mechanic..she can help me perform any mod I'd need to pass...I know, I'm a lucky guy

Thanks again for the info guys.
Will check thru the PowerFC forum for sure.

-jasonic

 

Your wife is the mechanic? Quite the role reversal there.

This thread describes what should be done - https://www.rx7club.com/showthread.p...&highlight=CEL . It makes the CEL come on when you start the car, which is what the technicians look for. It's a pain in the *** but you only have to do it once and it worked like a charm for me.

 

Role reversal?..LOL

I haven't told you what I do for a living

-j