I took my car in for its annual inspection a week ago and failed the (2-speed idle) emissions test. My first thought was self-recrimination at having removed the SAI pump and related plumbing from my 95 earlier in the year. Even though everything I had read said that the SAI only affects things for a short while after cold startup, it certainly seemed like too much of a coincidence that the first time I failed emissions testing was right after removing the SAI system.

But the guy doing the test asked whether I had been driving the car much, and as it turned out, I had hardly driven the car during the past month (and then only for short errands). I put in a bottle of fuel system cleaner, used up a tank of gas trying to blow the system out (which isn't that easy on busy public roads), changed the oil (which was due anyway), and took it back today for reinspection.

This time it passed with flying colors.

I was worried that my daily driver with 103,000 miles that doesn't really get worked that hard was in trouble, but all it needed was a chance to roar a little.

 

Black bottle Chevron Fuel Injector Cleaner has been my SOP for the "tank before smog" for almost 20 years. Redline's good too.

 

Probably the most important thing to do before a smog test is to get the engine, and especially the cats, up to full operating temp. I usually drive a fair amount before the test and let it idle before they take it.

 

One of perks of having a C4. The State emmisions station doesn't have a 4WD dyno short enough for a AWD C4, so I get an easy-cheese-lemon-squeezy test. Otherwise I am sure it would have failed. As I know the O2 was bad, the check engine light was on just the bulb was missing.

 

In Maryland, if your car is low enough, they will give you a two year waiver. Considering how little I drive my car, that makes sense.

 

I probably overdid it a little between the first test, and the re-test. I suspect that if I had just been driving it regularly, it would have passed the first time. But now I can rest a little easier knowing that I passed without my SAI system.

 

I use BG products after a very comprehensive lecture at Porsche Club meeting reviewing such products.........

I use 44K Power enhancer and CF5 fuel conditioner to keep things clean.........found it to be more effective than Techron........buy at most dealers......not available retail....can buy online also via ebay.........

I also use BG's MOA as an oil additive package......no issues.......makes the oil more slippery longer......less friction and wear......saw a great demo on the internals with a small motor's operation that showed a lubrication comparison with synthetic oils with and without.....

 

Hot engine definetly runs cleaner. Took the family truckster in this week, drove just under 10 miles to smog station from cold, HC and CO passed but NO measured 631 (fail) and 557 at 15mph and 25mph respectively. (max allowable shows 508 at 15mph and 761 at 25mph)

Took it on the road for 10 minutes and brought it right back, NO measured now at 101 at 15mph and 98 at 25mph - Pass! Lesson to self, make sure car is fully up to temp before smog test.