After working on alot of Aircare repairs I've seen some cars to be extremely tempermental. Especially a vehicle equipped with a non catalytic exhaust sytem and carburetor. Now by stating this I am putting a time stamp on this type of car...YUP ITS OLD. There are so many variables that will make a car fail.
Now for cataytic newer cars I see people shutting off the engines at the line. Thats not a very intelligent thing to do cause the catalytic will cool down and as you sit for a long time the car will get \"cold\" and go into open loop running rich. Hopefully as the car goes on the dyno it will reach its engines operating temperatures but still why chance it especially for a car with an older tired catalytic.
A technician at a local garage can look at your cars exhaust and look at the HC and CO readings but if they do not pay particular attention to the oxygen readings the HC and CO readings may be fudged on the Aircare test papers cause Aircare will determine if the exhuast has an exhaust leak. Aircares program changes so frequently that they have different procedures for old cars and newer cars.
Hey James what did the \"mechanic\" do to determine its gonna run clean?
computer? do you mean gas analyser?? The North Van Aircare center was shut down an entire day about a month ago due to some major computer failure. The following day they made all the cars going in the test to do a LONG TEST meaning driving the car upto 90km on the dyno. Usually they do the LONG test for questionable or failing cars. Even though my 67 beetle with original 75,000 miles runs extremely clean they made me go through the long test. Aircare does have some issues.
