sufficient gasket material I need to hand-cut my gaskets. I drove all over town this morning for 3 hours and EVERY speed shop I know is now closed on Saturdays and the stuff NAPA, Checker, Auto Zone et al sells is pure crappola. I'll hold out for the Mr Gasket stuff I've used for decades and get it from my favorite speed shop Monday morning. Damn good thing "every day is Saturday" for me!

And wouldn't ya know it, when I got home I stopped off at the mailbox and had received my plate/registration renewal notice in the mail and I'm due for an emissions test this time before they'll issue me plates/registration. No way my car will pass emissions with an intake leak at idle! So now I'm on the clock to get this done. Ain't it just always the way!?! Perfect, jus friggin PERFECT!!!

we have emission tests here (Ontario) as well, every 2 years.

The way we all defeat it is to put twice the regular amount of gas line antifreeze in a 1/2 tank of gas. Give her a good highway run to get her good and hot.

Has worked for many of my friends with ****box cars, and also on my 1993 12V.

As I said, I am sure you can elaborate on the pros/coms of this but just thought I would give my 2 cents.

more fuel from the ECU to try and cure the lean condition. And the ECU is POURING it in by the wheelbarrow full in an attempt to shut the sensors up. Without any intake leak I pass the rolling 4 wheel dyno with flying colors without resorting to anything beyond a recent oil change and the car fully up to operating temp when I arrive.

Only way to fool the tailpipe sniffer on this one is to fix the leak. Left as-is and unrepaired I would expect to have "thru-the-roof" NOx readings at idle... probably somewhere near double/triple the maximums allowed. 2 pints of ethanol (gas line antifreeze) ain't gonna make that go away especially when the gas pump is already putting in 10-15% ethanol blend every time I fill up!

I just reset my codes before i go in, and it passes EVERY time...

up the tailpipe and at all speeds from idle, off-idle and acceleration/deceleration up to and down from 75MPH. This is an "emissions test" and not a scan for OBDI/OBDII resident codes that haven't been cleared. They don't care about stored codes. In fact you can pass the emissions test with a CEL on as long as the emissions coming out the tailpipe are within allowable limits. But they will fail you on the visual inspection if you do not have a working CEL when ignition key is turned to "on."

I think I May have a small vac leak that I can hear as the engine decelerated form a rev to the throttle by hand. Engine runs fine and I can not find the possible leak, even with a stethoscope and "funnel" attachment for the stethoscope.

Funny thing is, this sound/leak happened after my new P&P'd I.M. as well.

We have tailpipe sniffing in PA but they just do it in neutral...

does the 4 wheel dyno thing and EVERY testing station has "at least" one 4WD dyno.

If you live in the mountains or west of the mountains you're exempt from emissions testing. But all along the front range, ie: Colorado Springs, Denver, Boulder, Loveland/Ft Collins you must pass a dyno emissions test every 2 years unless you have a pre-1972 vehicle.

Take a vacuum reading at idle after reaching normal operating temp. If you can't get at least 16 inches you've likely got a moderate intake leak and likely wont pass a tailpipe emissions test. Also if you have a miss or stumble on immediate WOT at the TB pulley it's likely due to a vacuum leak. If you twist the throttle pulley as fast as you can to WOT and any amount of faltering, miss, stumble or hesitation occurs somethings amiss.

99% of emissions testing facilities here only have 2 wheel dynos. The remaining 1% being Porsche dealers and the such.

If your car is full time 4 wheel drive you can still go to any faculty and get a "idle" test due to the 2 wheel dyno.

Every 2 years take the wife's FWD 93 to Canadian Tire for a emissions test, hand the keys in and then proceed to go back to my car to wait for the "tech".

When said "tech" arrives (16 year old apprentice) I remind him that this car (FWD) is a Quattro and if he runs it on that 2 wheel dyno there is going to be some BIG problems with this 35K car, lol. (gotta love the look of a 15 year old black and waxed 90!)

I have 2 in a row emissions tests (4 years) form "crappy tire" that say Audi 90 Quattro on them. Car is requested as a simple Audi 90 CS. Licence office does not care. all they care is that the vin number on the test matches the car and that the test says pass.

no dynos that I know of.

CO is stricter than CA!

I had to go to a 'Test Only Station' (They are not allowed to do repairs) the last two times the car was due for a smog check. I have never failed the smog test, but my car, according to the smog check "invite," fits the "high emitter profile."

i bet it would take half the cars off the road..

and I've considered it for a very long time. But the older I get the more conscience I develop and I take my bi-annual testing as a challenge to get all my clean-burning ducks in a row. Keeps me honest and I sleep nights doing it this way. I'm no tree-hugger but I like to do my part in leaving the planet in better shape than it was when I arrived. Same thing I do when in a wilderness campground. Wasn't always that way and I pity the poor folk that cleaned up after us and one of our little weekend sojourns in the U.S. Forest when I was 19 or 20. We took EVERYTHING "in" and NOTHING "out."

<center><img src="http://www.picoauto.com/tutorials/images/emissions_1-0.jpg"></center><p>
also used as the signal for the -variable- fuel pressure regulator (VFPR); and

Since the VFPR may need maximum vacuum in order to deliver the reduced fuel pressure at idle (and also during over-run conditions!) that the engine could otherwise (i.e. with no vacuum leaks) best use, the VFPR may be "helping" to supply that extra fuel.

Ordinarily (again, with no vacuum leaks), high engine vacuum will allow the VFPR to do the secondary part of it's job and further reduce the -default- higher full fuel pump pressure (designed to exceed peak requirements at WOT, co-incident with zero manifold vacuum), allowing that excessive pressure (as far as idle is concerned) to be bled off back to the tank via the return line. The beginning of the return line is (see vertical green arrow above) exactly where the VFPR sits, as gate-keeper.

I wonder if this (undiscovered vacuum leak) is, in part, one of the root causes for the burbling/back-firing on over-run that some have heard and Mance described here (see link below)?

Perhaps many of us need to fix these vacuum leaks and restore the full range of "variabilty" back into the VFPR?<ul><li><a href="http://forums.audiworld.com/12v/msgs/30893.phtml">55lbs of cure instead...</a></li></ul>

atleast not that i could see at this time..