SMOG: Machine read to much o2 and wouldnt even fail it. HELP :cry:

[ask92]

So i have a 89 turbo. It is 100% stock besides:
-3" CX intake pipe with the stock AFM and HKS filter
-3r muffler(rest is stock)
-hard pipes with a XS bov
-mbc

The car is throwing a TPS and knock code. I went and adjusted the tps with a multimeter today, but its still throwing the code. I also did the knock sensor rewire but i still get a 52(i do have a slight knock when its cold though, i think its just a pulley however).

Anyway i took it in, he told me how i was gonna lose my car because i have a mbc, blah blah..then tried to test it. It came back saying there was to much oxygen coming out and the machine couldnt read. I dont have any major leaks, and the car is running decently. I will be pulling the exhaust tomorrow to check out the cats. Anyone have any suggestions or help? thank yo.

 

[supraguy@aol]

Never heard of too much Oxygen.
And what did he mean you'd lose your car due to an MBC?

 

[bioskyline]

sounds like tester is having a derp session. to much o2 would indicate lean conditions.

found this on another fourm http://www.thirdgen.org/techboard/tbi/524810-too-much-o2-exhaust.html
might be some things to look into,

 

[ask92]

Because apparently the CHP(California highway patrol) is beginning to train officers for visual inspection right on the side of the road. And since my MBC is mounted on the strut tower it would cause them to confiscate the car. Not impound, they just take the car and sell it at auction. But right now this is only happening in southern CA. I will just move it to the glove box.


Yea he said its due to an exhaust leak(which i dont have) or the cats are bad.

 

[bioskyline]

ouch thats crappy.

could be bad cat, If there is too much oxygen in the exhaust, the preferential reaction in the catalytic converter is the oxidation of CO or hydrocarbon rather than the reduction of NOx.

 

[dubsupra209]

Because apparently the CHP(California highway patrol) is beginning to train officers for visual inspection right on the side of the road. And since my MBC is mounted on the strut tower it would cause them to confiscate the car. Not impound, they just take the car and sell it at auction. But right now this is only happening in southern CA. I will just move it to the glove box.


Yea he said its due to an exhaust leak(which i dont have) or the cats are bad.

what? thats wack you got a link to the new law?

 

[ask92]

No i have no idea if its factual or not, i'm just reapeating what he told me. I honestly don't doubt him(he told me that a bunch of CHP officers are now taking the visual inspection classes that he takes) but I'm sure they only take your car and auction it under EXTREME circumstances(street racing, ect)

 

[supraguy@aol]

That is insane.
Put a Homedepot $6 boost controller on a car, and they take your car away?
Unbeleiveable.

 

[mk3_7m]

:O well i find that a load of bull law. I might as well plant a c-4 on the car when auction day happens.

 

[grimreaper]

if that law is true.. there is bound to be a "cop shot over car" story at some point in the future..:yikes: reminds me of the old "count the cents and watch the dollars" form of business financials but applied towards saving the environment.

 

[Nick M]

Because apparently the CHP(California highway patrol) is beginning to train officers for visual inspection right on the side of the road. And since my MBC is mounted on the strut tower it would cause them to confiscate the car. Not impound, they just take the car and sell it at auction. But right now this is only happening in southern CA. I will just move it to the glove box.


Yea he said its due to an exhaust leak(which i dont have) or the cats are bad.

Move to rual Texas.

 

[ask92]

"Well theres your problem" Good ol previous owners....

 

[jetjock]

Except that has nothing to do with your problem...

 

[Poodles]

Except that has nothing to do with your problem...

Beat me to it.

 

[jetjock]

The likely explanation is he got the gas wrong. Sort of makes the entire thread a waste of time but since that's probably what happened the irony is, assuming the engine is in fuel control, the new cat probably will fix it...

 

[ask92]

Doesn't the cat use the o2 coming out of the engine and use it to get rid of the other toxins? That is what the smog shop owner told me in better terms than i used, and as he has been doing smog for over 10 years and been a tech for 30, im gonna just guess and say he knows his emissions stuff.

I had to much o2 in the system AND im sure i had to many other gases as well, but the high o2 is what made the machine not be able to complete the test.

 

[Poodles]

Doesn't the cat use the o2 coming out of the engine and use it to get rid of the other toxins? That is what the smog shop owner told me in better terms than i used, and as he has been doing smog for over 10 years and been a tech for 30, im gonna just guess and say he knows his emissions stuff.

I had to much o2 in the system AND im sure i had to many other gases as well, but the high o2 is what made the machine not be able to complete the test.

No...

 

[jetjock]

He's right about using O2 but some other things don't add up. First, the composition of a stoichiometric exhaust stream sans catalyst contains little oxygen to begin with. Therefore the cat being empty has zero bearing on there being too much. All the empty cat would do is pass what O2 is coming out of the engine directly to the analyzer and that normally isn't much.

Second, since the analyzer can measure oxygen to atmospheric level, the machine won't normally over-range even with ambient air being drawn into the exhaust plumbing. To say it couldn't read all the O2 doesn't make sense because it's capable of reading all there is (20.85%) in the air. Otherwise it wouldn't be very useful as a diagnostic tool.

However, since the test is automated, it's possible the machine is programmed to abort the test beyond a certain level of O2 although I've never seen that happen. It still doesn't explain where all the oxygen came from though, unless you had huge exhaust leaks, the test wand wasn't in the pipe, or the engine was running extremely lean, which would be very obvious. But for sure it didn't come from having the cat hollowed out.

It's that or you got the gas he was talking about mixed up...

 

[ask92]

Good info jetjock. But i know i don't have any major leaks, and i know he said o2 as i questioned him immediately on it. The car idles, drives and boosts perfectly, which leads me to think its not lean. It actually smells pretty rich to me as well at idle. He did say that if he had more time with the car he would put the machine into manual and check everything himself because he didnt see or hear any leaks, and the car was idling fine.

 

[jetjock]

Yeah, the machine can be used to do smog tests or emissions diagnostics, the "manual" mode you're talking about. What happens during a test is more complicated.

There's another problem with what you posted though: O2 and rich mixtures don't go hand in hand. You can't have a rich mixture and have high O2 unless the O2 is getting in from the outside. Something is goofy.

You need to get that figured out because if the engine out exhaust stream isn't near stoich your new cat will not only fail to work well but could also have its life shortened. Make sure the engine is running right before installing it.