VA - No more sniff!

Post by **ElZorro** » Mon Aug 29, 2005 3:34 pm

The testing site that I was at today did just OBDII, no sniff. I asked the tech and he said that the state approved just OBDII back in July and the testing sites have been slow to roll it out. I went to the Mobile near the intersection of Elden and VanBuren in Herndon. Tech did no visual inspection for cats (the car is essentially stock though, nice and quiet) and did the brake/wheel checks without taking off the wheels (first time I had seen that).

sirwilliam · Post by **sirwilliam** » Tue Aug 30, 2005 1:12 pm

ElZorro wrote:The testing site that I was at today did just OBDII, no sniff. I asked the tech and he said that the state approved just OBDII back in July and the testing sites have been slow to roll it out. I went to the Mobile near the intersection of Elden and VanBuren in Herndon. Tech did no visual inspection for cats (the car is essentially stock though, nice and quiet) and did the brake/wheel checks without taking off the wheels (first time I had seen that).

Not that I wouldn't pass but will have to go there!

Mr Kleen · Post by **Mr Kleen** » Tue Aug 30, 2005 1:43 pm

this was a topic at our table last night. just about the time I'm going Stage 2 they change the tests. I have until next May to figure out how to beat it...

sirwilliam · Post by **sirwilliam** » Tue Aug 30, 2005 1:50 pm

Mr Kleen wrote:this was a topic at our table last night. just about the time I'm going Stage 2 they change the tests. I have until next May to figure out how to beat it...

Stage 2 shouldn't be a problem w/ emissions unless you go catless.

Mr Kleen · Post by **Mr Kleen** » Tue Aug 30, 2005 3:42 pm

I'll be leaving the #3 cat in place. as I understand it the problem is that the second O2 sensor will throw a CEL, which my accessport will suppress but it might still be possible for the tech to see the CEL and know there is a "problem." a possible fix is to use a spark plug anti-foul fitting to back the O2 sensor out of the exhaust gas stream. again, this is my understanding from the conversation over dinner last night at HTs. more investigation might be necessary, or maybe I've just got the story all wrong

sirwilliam · Post by **sirwilliam** » Tue Aug 30, 2005 3:52 pm

Mr Kleen wrote:I'll be leaving the #3 cat in place. as I understand it the problem is that the second O2 sensor will throw a CEL, which my accessport will suppress but it might still be possible for the tech to see the CEL and know there is a "problem." a possible fix is to use a spark plug anti-foul fitting to back the O2 sensor out of the exhaust gas stream. again, this is my understanding from the conversation over dinner last night at HTs. more investigation might be necessary, or maybe I've just got the story all wrong

Okay for some reason I thought you had an STi...WRX is different.

hotsam · Post by **hotsam** » Tue Aug 30, 2005 9:57 pm

Get yourself a Perrin O2 Simulator and never throw a CEL again...

Mr Kleen · Post by **Mr Kleen** » Tue Aug 30, 2005 11:40 pm

again, this is knowledge filtered through conversation at HTs over very loud music and lots of chili: the stock O2 sensor shows a changing voltage (resistance?) depending on throttle position. a resister mod can be detected by a smart tech during the OBDII testing. or something like that.

we need to have this conversation in person and with the guys who actually know what they're talking about. I get the gist of it but I'm not sure I'm relating it correctly.

somebody jump in and save me from myself.

Post by **Sabre** » Wed Aug 31, 2005 12:07 pm

Not that I know any who can program a PIC <cough>Jason</cough>, but this would be a simple exercise of programming...

Post by **ElZorro** » Wed Aug 31, 2005 2:25 pm

Honestly, it shouldn't even be a microcontroller project, a freshman EE should be able to draw up a resistor diagram to handle it.

Post by **complacent** » Wed Aug 31, 2005 2:50 pm

uhhh... just spend the 1.49 and buy two spark plug anti-fowlers. or get either a Godspeed or Injen downpipe. Both will move the rear o2 sensor far enough out of the exhaust stream that readings will remain "within spec"

best 1.49 I had spent on the WRX.

See you let a pair of engineers plan out something simple and invariably one of them will try and find the most complex situation available. Then you ask an idiot like me and you'll find something a five year old might have come up with and it'll work. (sometimes)

Almost all electronic rear cat inefficiency fixes will cause the sensor to give a "sensor not ready" code, which is grounds to fail you on an OBDII test. With the mechanical fix above, you could actually drive in catless and roll out with a pass.

just my .02USD

Post by **ElZorro** » Wed Aug 31, 2005 3:21 pm

bluscooby23 wrote:See you let a pair of engineers plan out something simple and invariably one of them will try and find the most complex situation available. Then you ask an idiot like me and you'll find something a five year old might have come up with and it'll work. (sometimes)

It's all about justifying the edjimucation.

Post by **Sabre** » Wed Aug 31, 2005 3:30 pm

What do you mean? I went to school to drive trains and they threw all this math crap at me....

Mr Kleen · Post by **Mr Kleen** » Wed Aug 31, 2005 3:56 pm

bluscooby23 wrote:uhhh... just spend the 1.49 and buy two spark plug anti-fowlers. or get either a Godspeed or Injen downpipe. Both will move the rear o2 sensor far enough out of the exhaust stream that readings will remain "within spec"

Zak said that the anti-fowlers would corrode over time and should be replaced yearly. my grandfather is a retired master machinist with a nice workshop in his basement. maybe he could machine something to match the anti-fowlers out of a material that wouldn't degrade?

AJ711 · Post by **AJ711** » Fri Sep 09, 2005 2:50 pm

Mr Kleen wrote:
bluscooby23 wrote:uhhh... just spend the 1.49 and buy two spark plug anti-fowlers. or get either a Godspeed or Injen downpipe. Both will move the rear o2 sensor far enough out of the exhaust stream that readings will remain "within spec"

Zak said that the anti-fowlers would corrode over time and should be replaced yearly. my grandfather is a retired master machinist with a nice workshop in his basement. maybe he could machine something to match the anti-fowlers out of a material that wouldn't degrade?

Make it the same metal that the exhaust system is, and you won't have to worry about corrosion (as much). Using disimilar metals will just increase the likelyhood of rust and things.

Mr Kleen · Post by **Mr Kleen** » Fri Sep 09, 2005 3:24 pm

aren't most UPs made from Stainless Steel? I think SS is pretty hard to work with so this may not be possible. I actually didn't even install my UP this weekend because I realized that it didn't have an O2 bung at all. I decided that discretion was the better part of valor and just did the DP and put anti-seize on the UP bolts. baby steps...

drwrx · Post by **drwrx** » Fri Sep 09, 2005 4:23 pm

Sorry I'm late to the party guys.

Here's the issue: The OBDII test is simply a hook-up and run test. If your clear of cels you pass.

However, if your ECU indicates that it was cleared prior to a full cycle (ECUs have a varying amount of time between cycles) the tech can wait-out the cycle before passing you. This will catch all those who run catless with out a fix. That being said, the only issue we have (emissions wise) is with the rear O2 sensor. If you use an in-line resistor the sensor will only see a constant voltage. If the tech runs a "full" diagnostic while applying the throttle, the O2 sensor should read the rising rate and indicate that fluctuation. With the resitor in place, it will stay steady regardless of the throttle. The tech will know and the jig is up! The anti fouler beats this as it does take a reading, albeit a false one, that will rise and fall with thottle application. There are no problems with using the resistor for the up-pipe sensor as it is simply a dumb switch.

You could attempt to coat the anti-fouler with a high temp anti-corrosion paint. 800-1,000 degrees is probably more than safe, and it should last for some time.

zaxrex · Post by **zaxrex** » Fri Sep 09, 2005 4:28 pm

That bung on the up pipe (before turbo) is the EGT probe. The O2 sensor is in the exhaust manifold by the right front wheel.

When you do take the up pipe out to replace it, get and in-line ceramic 2.2kOhm resistor from Radio Shack and stuff it up in the connector that the probe used to plug into. The resistor fools the ECU into thinking everything is happy.

drwrx · Post by **drwrx** » Fri Sep 09, 2005 4:48 pm

I have a bunch of them. Let me know when you switch it out and I'll give you one of mine and show you how to install it.

Mr Kleen · Post by **Mr Kleen** » Fri Sep 09, 2005 4:55 pm

OK, starting to get an idea of what's going on now that I've spent a day under the car... I have the resistor and a Bosal UP. guess I just need to install it now.

I have more questions but will have to wait till the next meet because I'm too lazy to type them out/try and explain them.

as always: thanks for the help!

DCAWD.com

VA - No more sniff!

VA - No more sniff!

Re: VA - No more sniff!