Hello.

I have a 1997 Porsche 993 normally aspirated car that doesn't want to reset any of the readiness codes. It shows two persistent heater errors for a flap and a sensor but thats all that is on the computer. No DME faults. I took it to the dealer and they did the short tests for secondary air and evap and both work fine

I also drove it about 100 miles and did the recommended drive procedures for idle and rpm control several times.

Any ideas and has anyone see this problem before. I had to disconnect the battery when doing a bunch of service, but didn't think to check for readiness prior to disconnecting. I cleaned out the secondary air injection system and put in new parts since the engine was out. All ports flow nicely. I replaced all the vacuum lines as well along with distributor belt, plugs, wires, clutch, chain tensioner housing gaskets etc. Car runs great and better than before.

Any advice or ideas appreciated. I posted this on Pelican as well. Just looking for solid advice if you have some.

Thank you.

 

Read here under 'Porsche 993 Cycle Flag Basics'; http://www.systemsc.com/codes.htm

 

my 97 takes two consecutive perfect drive cycles to reset. maybe re-read the procedure and try again.

salt lake county now has sniff testers at most stations that do not require rollers, so when you get it tested and the person says you failed ask to pay for a sniff test. that will give you something to show the person at the referee station.
if you are outside of salt lake county I don't think they even care about obd2, just safety inspection.

 

Where is Snyder's Mill, near Park City?

While Loren's site gives you the details of what is happening, twice through this detailed drive-this-fast-in-this sequence process works (posted by jackb911):

Start engine (cold start), let idle for approx. 2 min, 10 secs.
Accelerate to 20-30 MPH, Maintain steady speed for approx 3 min, 15 secs.
Accelerate to 40-60 MPH, Maintain steady speed for approx 15 mins.
Decelerate and come to a stop. Then:
Idle in Neutral for 5 mins. (manual trans.)
Idle in Drive for 5 mins. (Tiptronic trans.)
During the drive cycle, do not exceed 3,000 rpm or 60 mph.

I've been through this many times. It doesn't have to be done in the exact sequence (except the cold start of course). If you get interupted by a stop light or such just continue when you can. You cannot shut the car off (or stall it) or you have to begin again with a cold start.

I've been through this many times. Let me know if I can help.

 

Hi there.

It is before Park City on 224.

I have done the drive cycle numerous times and normally one drops off followed by another etc.

Just no change. I will keep on driving it and see, but its been over 100 miles so far.

Thank you.

 

If your car is an early build 97, it could have a 96 ECU. These can be a little finicky, but a few careful drive cycles should do the trick.Good luck.



Emerald

 

What tool are you using to read the readiness codes?
There was a problem with an older version of Durametric software which would show the flags not ready, when they were actually ready. Newer versions of the software are fine, so if that is your problem, just download the update. I encountered this issue with my 97.

 

Using factory Porsche PS2 tester and the later one they upgraded to. I can go through the short tests on secondary air and evap and they appear fine. Just frustrating. I will try driving more. There is not check engine light on and no errors that I can see.

 

You wouldn't happen to be above ~7500ft elevation by chance?

 

Hmmm. Park City is about 7000'.

 

Is this drive cycle right out of the factory service manual? I'm seeing several suggested drive cycles on the 'net and hearing something different from the smog shop guy. Thanks.

 

Take the one that I posted under my user name. It worked 2x for me. You need to buy a cheap obd 2 reader to verify the results. This is money well spend.

 

with the factory PST2, you could set the readiness codes in a breeze
follow the factory procedure with the PST2 and you will be fine

http://www.pcarworkshop.com/images/d...93-1997-07.pdf

 

"with the factory PST2, you could set the readiness codes in a breeze"

Not really. It only facilitates setting the SAI and tank venting monitors.
It still requires a driving process but one can easily check as each monitor
is set within a drive cycle. It can also help determine when a drive cycle
is complete and, thus when the next drive cycle can be started.

 

Look here for simplified version of the drive process. I did it twice and then everything was hunky dory. As 39estibi says, get a cheap code reader that will tell you when the computer is set (or reset) so you'll know when you're successful.