I have a neighbor who says he took his son's 993 for emissions,and was told the readiness codes are not set. This car has been driven from Texas to Tennessee,and around for a couple of weeks before going to inspection. He says there is no CEL and no fault codes. Is this possible,and what would anyone suggest as to the cause of readiness codes not setting. I'm baffled.

Thanks,
Emerald

 

Did your neighbor's son just acquire the car (from Texas?) or has he owned it for a while? If he just bought it, perhaps the PO changed/disconnected the battery, which would set all codes "not ready". One could easily drive several weeks thereafter without re-readying the codes. Let us know.

 

It was recently purchased.

Thanks,
Emerald

 

The codes haven't all become ready because he hasn't run through all of the drive sequences yet. There are a series of somewhat specific driving conditions that must be executed so the computer can do it's diagnostics test and "ready" the codes. I find (and am going to have to do it again now for my registration) that a couple of long drives along with a couple of stop lights does the trick. The cycles only start from a dead cold start and break even if in the middle of a test until the entire test can be performed all at once. If the car is just doing short stoplight to stoplight runs, even with the long trip, the conditions are not being met to complete the tests.

I'm sure someone will chime in with links to the specific sequences that are needed. I personally have never found them to work. I used to use my track weekends to take care of things, no just have to rely on a couple of small road trip type drives to get "readied".

GL with it....

 

Recently purchased....Are you sure the seller did not remove the cel bulb?

 

I am fighting the same problem. No CEL but no pass the state computer either. Tried the Porsche driving pattern but probably screwed it up. Stopped at Reid-Vann and they said just to drive it for about 20 minutes at or below 2800 rpm with emphasis on not exceeding the 2800 mark. Have not done it yet so I really hope it works.