I have a 93 RX-7 and recently tried to smog it. It failed because the HC went over by 2 points. Max is 37 but measured was 39 at 25 mph. Any tips on how I can fix this?

Additional information is that I replaced the spark plugs and did an oil change before the smog.

 

replace cats or source out a good know oem set. it targets the hc's. only other thing you can do is tune up and look for vacuum leaks.

 

PM SIRINIKO for Smog hookups!

He helped my 87 Accord pass with flying colors!

 

hope this helps, i got state reff'ed so none of that shady stuff

https://www.rx7club.com/west-rx-7-forum-193/state-ref-991425/

 

How about a little bit of denatured alcohol? It should lower your HC so you can pass ref.

 

Fuel Injector cleaner is another alternative. Point, to the extent you're not burning Dino gas you're not producing Dino HC's.

 

no doesnt work.

 

that doesnt work either, if you just pour it in before you go it will fail.

 

So this is the only way!?

I passed 2 years ago with this current setup. Wonder what is causing the small change in HC.

 

always check for vacuum leaks

 

take it back on a hotter day and fully warm it up and leave it running before the test.

2 points is 2 points, nothing magical but add a little more heat to the converter and it will pass. they should pass it on merit, it did try and came damn close...

 

id have to see the smog report but if it passed hc at 15 and didnt pass hc at 25 then your problem is going to be electrical(plugs and wires) if the hc's are insanely out of bounds then id say take a look at the cat but so long as the nox is in bounds your cat is good! if it has a down stream o2 sensor then try n see if you can hook up an oscilloscope to it. It should read flatline whereas the upstream will toggle as usual. that will let you no if the cat is good! its hard to kill a cat unless your engine runs dirty(burns oil n too rich).

 

a downstream O2 sensor? i think you logged onto the wrong forum.

 

I could vouch for that!

 

yeah ive yet to own an fd i only got a gsl, gslse, and GTU and they are all anolog so i dont know about the fd's n i take it its a 93 so it probably doesnt since it only comes with an 8 bit

 

check you PCV value.

 

don't get all crazy trying to diagnose anything, if you blew on the tailpipe while it was running the test it would have brought it down those 2 points. i'm really surprised the smog tech didn't just offer to rerun the test.... but you know, people just don't give a **** these days.

 

Where in the bay are you?
Did you warm up your car before you brought it in?
Do you know if they tried to run it twice, or just once?

 

ben, you do know legally, as a smog tech, we dont have to run anything twice, specially not if it means helping a car pass......thats illegal..........
now, if you wanted to check to see if itd pass, ask to have a pretest done. then, if it doesnt pass, pay for another one. nice part about that is that a pretest doesnt get sent to the dmv/bar, and if it passes the second time, then have the vehicle run on the normal test right then. bam, should pass.

2 points on the hc isnt uncommon, and a fail is still a fail.
like i said, a pretest should take car of it. its absolutely absurd how low the limits are for some cars, but not others......
oh well, welcome to the soviet state of california. if youre in the east bay, hit me up, i can take a look at it for you, 100% legally, nothing shady

Lloyd

 

i know you don't have to run the test twice but offering to run the test twice consecutively isn't against any rules that i know of. of course paying for 2 tests is still cheaper than gas and diagnostics running multiple tests.

 

i know you don't have to run the test twice but offering to run the test twice consecutively isn't against any rules that i know of. of course paying for 2 tests is still cheaper than gas and diagnostics running multiple tests driving to and from house or repair shops.

who knows, maybe they changed the rules. back in the day we could test a single car 100 times in a day if it kept failing. no cali smog tech ever told me it was against any rule.

 

oh you can run a car as many times as you want in a row, if you want bar coming down and investigating. it makes it look like illegal activity is going on. most smog techs, including myself, will not run a car twice in the same day, at least within a few hours of each other. the laws and rules are getting more and more strict, to the point now where if you mess up smogging a car, it shows up in their database and is held against you, if it happens enough, they investigate.
plus, with the state going with the star program, if you mess up a lot, its nearly impossible to get a smog job, cause shops wont want to hire you because it will effect them and business.......
***** getting insane. its why im trying to get out of dealing with smog and only dealing with racing fab, engine building, **** like that

Lloyd

 

Thanks for all the input guys!
I did warm up the car before the test. Would be nice to have one of you guys take a look at it. I'm in Daly City so if anyone can just let me know.

Hey Ben! Remeber me? Haven't seen you since you moved down to LV.

 

Pm me your number. I'm local.

 

ya our shop is kinda like this, we can run as many pretest on a vehicle as we want but once you enter it in the computer and it gets sent out my boss says only do it once if its that bad but if its close to passing by a couple points and we know whats causing it and fix it we will run it again but its gotta pass so we gotta be sure its the problem. haha yeah i trip out on some of the techs who cant hold it in the lines steady at 15mph and the boss gets pissed