2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

Failed Emissions S5 na

Old 03-27-15, 05:53 PM
  #1  
S5 GXL NA - S5 TII

Thread Starter
iTrader: (2)
 
Kenshin XI's Avatar
 
Join Date: May 2010
Location: Colorado
Posts: 330
Likes: 0
Received 3 Likes on 3 Posts
Failed Emissions S5 na

My FC failed emissions since I need to set the timing, tps makes the idle bounce around, and probably because the air pump doesn't have a belt on it (adjuster bolt snapped). I put on a cat/resonator that I used last emissions test and have only used it for the tests so the cat isn't bad. Would the timing off and air pump not working properly give that high of a reading or is there other things that I should be aware of that could also be in play?

Failed Emissions S5 na-fc-emissions.jpg
Old 03-27-15, 06:02 PM
  #2  
Full Member

iTrader: (1)
 
MjhRotor's Avatar
 
Join Date: Jun 2009
Location: Phoenix
Posts: 149
Likes: 0
Received 0 Likes on 0 Posts
A properly functioning air pump is vital to passing emissions on these cars make sure its hooked up and your air control valve is properly diverting the air.
Old 03-27-15, 06:18 PM
  #3  
Rotary Enthusiast

iTrader: (1)
 
barkz's Avatar
 
Join Date: Sep 2011
Location: New Hampsha
Posts: 1,261
Likes: 0
Received 1 Like on 1 Post
Failed emissions without a working air pump? You don't say...
Old 03-27-15, 06:35 PM
  #4  
S5 GXL NA - S5 TII

Thread Starter
iTrader: (2)
 
Kenshin XI's Avatar
 
Join Date: May 2010
Location: Colorado
Posts: 330
Likes: 0
Received 3 Likes on 3 Posts
The problem I have with the air pump is that the bolt is snapped to tighten the belt so I took off the belt. The pump is still on though. I don't know if there's anything else I could use to tighten it in place so I could have the belt back on to run it.
Old 03-27-15, 09:11 PM
  #5  
Moderator

iTrader: (3)
 
j9fd3s's Avatar
 
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,778
Received 2,563 Likes on 1,823 Posts
it needs the air pump. then set the idle speed, bouncing is probably bad.

then it should pass, 220hc's is pretty generous
Old 03-28-15, 09:43 AM
  #6  
Senior Member
iTrader: (1)
 
spectre6000's Avatar
 
Join Date: Mar 2015
Location: Colorado
Posts: 356
Likes: 0
Received 1 Like on 1 Post
Your HC and CO are too high (no NOx reading?). High HC means incomplete burn, CO is the same. Because of the design of the rotor housings, some fuel from a charging chamber is able to make its way to the end of the power chamber/beginning of the exhaust chamber, and it makes for a pretty dirty burn. The air pump injects fresh oxygen into the still fairly charged exhaust gases and gives the unburnt hydrocarbons something to chemically react with using the heat of the exhaust gasses already present. In a nutshell, this is what the air pump does.

Mine is adjusted differently than yours it sounds like, but my AC compressor has an adjustment bolt. When I changed the belt last weekend, I discovered the PO bent it somehow, so naturally it simply snapped when I attempted to loosen it. I simply pulled it out and went to my favorite hardware store (McGuckins!) and got a new one. The new one was shouldered for the majority of its length, but I have a pretty comprehensive collection of taps and dies, and was able to make short work of it. If memory serves, you're looking for an M6X1.0 X 90mm bolt (naturally, assuming it's the same).

That will go a long way, but getting the rest of your house in order will probably also prove necessary. A basic tuneup should be done once a year at a minimum.
Old 04-03-15, 06:08 AM
  #7  
Retired Moderator, RIP

iTrader: (142)
 
misterstyx69's Avatar
 
Join Date: Sep 2005
Location: Smiths Falls.(near Ottawa!.Mapquest IT!)
Posts: 25,581
Likes: 0
Received 131 Likes on 114 Posts
Originally Posted by Kenshin XI
The problem I have with the air pump is that the bolt is snapped to tighten the belt so I took off the belt. The pump is still on though. I don't know if there's anything else I could use to tighten it in place so I could have the belt back on to run it.
Take the pump off and drill through the old broken off one.Then put a small "through bolt" in the hole.
Then put the belt back on.
Old 04-03-15, 11:32 AM
  #8  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by spectre6000
Your HC and CO are too high (no NOx reading?). High HC means incomplete burn, CO is the same. Because of the design of the rotor housings, some fuel from a charging chamber is able to make its way to the end of the power chamber/beginning of the exhaust chamber, and it makes for a pretty dirty burn. The air pump injects fresh oxygen into the still fairly charged exhaust gases and gives the unburnt hydrocarbons something to chemically react with using the heat of the exhaust gasses already present. In a nutshell, this is what the air pump does.
in a nutshell, rotaries don't burn fuel very efficiently! haha. no dwell. no time for atomization. just get it in and get it out! and without a working airpump that cat will surely fail in short order as well. so get on it quick!
i don't believe vehicles of an era equipped with only 2-way cats were required to meet NOx emissions standards. that would make sense to me anyways
Old 04-07-15, 08:17 PM
  #9  
Stuck On 7
 
Stuntman_Sucio's Avatar
 
Join Date: Jan 2012
Location: Jersey City, NJ
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
I was considering taking my air pump off. Can anyone tell me the pros and cons of doing so i have a inspection so im good to go as far as that goes. Any help is appreciated. Thanks
Old 04-07-15, 10:50 PM
  #10  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
most people remove it after installing an aftermarket exhaust, since the new exhaust typically won't have the provision for split air which the air pump provides. nor will many run a catalyst to make use of the air pump if it did. it also opens up space in the bay to make work easier. and reduces drag on the engine i suppose
Old 04-07-15, 11:08 PM
  #11  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
His S5 has no need of exhaust pressure, the airpump powers his 5th/6th ports.
Remove the pump and you lose function of those ports.
People seem to like wiring them open but report a loss of bottom end after doing so.
Or you could use an electric airpump.
I've worked with older Corvette airpumps and they seem robust enough but are about the same size as the stock Mazda part, so I don't think you gain much from a packaging perspective.
Old 04-07-15, 11:13 PM
  #12  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
ohhh yea. the actuators. i honestly doubt you lose much, if any, in the lower range with them open. my old s5 6port were open and that thing seriously screamed. stock ecm and injectors too
Old 04-07-15, 11:18 PM
  #13  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
i haven't driven a 6port with working actuators though to base a comparison. but this thing was pulling against my t2 though
Old 04-07-15, 11:22 PM
  #14  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Regardless of the consequences, I just thought he should know.
Old 04-07-15, 11:25 PM
  #15  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
nope. be quiet. he need not
Old 04-08-15, 12:28 AM
  #16  
Rotary Freak

iTrader: (1)
 
rx7racerca's Avatar
 
Join Date: Jul 2004
Location: Lake Country, BC, Canada
Posts: 1,725
Received 8 Likes on 5 Posts
I haven't driven with the 5/6 port actuators disabled/wired open, but I'm fairly certain that Mazda wouldn't have gone to the considerable expense and complication they add if they didn't deliver real benefit. NAs have little enough torque as it is, so unless the car is intended primarily for track use, or one is fine with keeping the revs high all the time, the loss of lower rpm torque is likely to be noticeable. It's the rotary equivalent of variable valve timing and lift in a piston engine.
Old 04-08-15, 12:36 AM
  #17  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
mmmm not quite. they're secondary ports. like secondary ports in a piston engine. all i ever hear about disabling them is people who say just what you said. speculation. mazdas primary goal is not always what produces optimal hp or torque values
Old 04-08-15, 01:00 AM
  #18  
Rotary Freak

iTrader: (1)
 
rx7racerca's Avatar
 
Join Date: Jul 2004
Location: Lake Country, BC, Canada
Posts: 1,725
Received 8 Likes on 5 Posts
In the case of the 5/6 ports, the goal specifically is, however, to deliver better breathing capacity at higher rpms, without having the engine fall flat on its face at lower rpms due to low intake velocity, and the poor chamber-filling and low torque that go with. Secondary ports is a better analogy, though.
Old 04-08-15, 01:59 AM
  #19  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
i get what you're saying. in theory, nothing but negative effects should be seen by keeping them open. which is why i can't explain why, but my old 6port s5 just sang like a canary, all through the band.
deleted actuators. exhaust. 12lb flywheel. cone filter. and a t2 trans. that's all. mazda reman, so i can't see any port work being done to that
Old 04-08-15, 06:59 AM
  #20  
Cake or Death?

iTrader: (2)
 
clokker's Avatar
 
Join Date: Jan 2007
Location: Mile High
Posts: 10,249
Received 63 Likes on 53 Posts
Originally Posted by welfare
i haven't driven a 6port with working actuators though to base a comparison.
Originally Posted by welfare
i in theory, nothing but negative effects should be seen by keeping them open. which is why i can't explain why, but my old 6port s5 just sang like a canary, all through the band.
Maybe with working actuators it would have screamed like a banshee instead of warbling like a songbird.
Old 04-08-15, 08:42 AM
  #21  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
you may very well be right. unfortunately the car was like that when i'd bought it, so i couldn't compare with and then without.
Old 04-08-15, 08:44 AM
  #22  
Senior Member
 
welfare's Avatar
 
Join Date: May 2010
Location: vancouver, bc
Posts: 535
Likes: 0
Received 0 Likes on 0 Posts
it was, however, far from warbling.
Old 04-08-15, 08:48 AM
  #23  
Stuck On 7
 
Stuntman_Sucio's Avatar
 
Join Date: Jan 2012
Location: Jersey City, NJ
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
I read on aaroncake that its a loss of 25hp above 4000 rpm. TThere is an easy way to check Them so i guess ill check to see if they work. if they dont work ill open them up till i can fix them to see if theres any real difference. My inital interest came from these rb headers i have which have the pick up tube for the actuator And i wasnt sure if the airpump had anything to do with the actuators. Thabks for the help everyone.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Turblown
Vendor Classifieds
12
10-17-20 03:25 PM
ls1swap
3rd Generation Specific (1993-2002)
12
10-01-15 07:58 PM
RedBaronII
3rd Generation Specific (1993-2002)
4
09-20-15 11:29 AM
JP's 93 fd
3rd Generation Specific (1993-2002)
5
09-16-15 01:12 PM


Thread Tools
Search this Thread
Quick Reply: Failed Emissions S5 na



All times are GMT -5. The time now is 09:00 PM.