Trouble Codes: Need help/suggestions/advice

[pessemist]

Hello all: I just purchased a mint condition 1999' 911 coupe with 100K miles on her.

After driving 200 miles I got check engine light with codes P1126, P1124 Also got the P0130* & P0150* as 'intermittent' codes. I rest them and almost exactly another 200 miles the exact same codes came back.

My research shows that this suggests the engine is running leaner than normal. But now I am not sure what to replace/fix.

I am thi9nking of the following progressive repair list (throw parts at it) until the light stays out:

ROUND #1
Replace oil cap
Replace Gas cap
Replace Mass Flow Sensor
Replace Air Filter

ROUND #2
Replace all Oxygen Sensors

ROUND #3
Replace all Spark Plugs

ROUND #4
Find a garage that is competent to do a vacuum check on the engine.


Does this sound like the right approach? All this stuff is likely due for replacement anyway. The engine is clean enough to eat off of so I know it was a garage queen and saw an easy life.

The engine itself sometimes runs rough for about 30 seconds (not always) but then settles down to a nice purr.

Thanks ahead of time for any help, advice or suggestions.

Doug

[Luccia at Pelican Parts]

Welcome to the Pelican community, Doug! You might get more help in the 996 section, so I've moved your thread to there. Some of our community members should chime in with some advice. The 911 tech section is mostly geared towards air-cooled 911's.

Don't forget to check out our tech articles for some help on diagnosing your issue as well - Porsche 911 (1998-2012) Technical Articles - Porsche 996 & Porsche 997 - Pelican Parts. If you comment at the bottom of one, our tech will come in with some advice for you. Good luck!

[tonythetarga]

Rather than starting to throw money at the problem, I'd suggest you find a competent independent shop that KNOWS 996's and start there. I would say you didn't get a PPI to start with and fell victim to the code clearing tactic which resets itself and then collects data after driving a couple hundred miles. Indicate your location in the country and you might get a recommendation for a reputable shop.
BTW, look inside your coolant tank and make sure it only has coolant in it.

[pessemist]

Originally Posted by tonythetarga

Rather than starting to throw money at the problem, I'd suggest you find a competent independent shop that KNOWS 996's and start there. I would say you didn't get a PPI to start with and fell victim to the code clearing tactic which resets itself and then collects data after driving a couple hundred miles. Indicate your location in the country and you might get a recommendation for a reputable shop.
BTW, look inside your coolant tank and make sure it only has coolant in it.

I kinda bought this older car with the idea of learning about it and doing some of the work myself. I am in the Toledo, OH area (zip 43606) if anyone knows a good Indy dealer? Because at some point I'll likely need him.

I do have a master mechanic I use, but he has limited experience with 996's.

If anyone knows a mechanic in Toledo, Ohio area with good experience working on 996's, let me know. There are a couple of large dealers, but I'm looking at a grand just to drive by their place. Numerous bad experiences. One place wanted $1,500 for a Chrysler 300 AC compressor installation while my independent shop found a broken wire and fixed it for $25.

In any event, she is about due for most of these replacements. Any specific ideas to suggest other than take it to a mechanic?

Thanks!

[Luccia at Pelican Parts]

Use this site to help you find a Porsche indy shop in your area: https://www.pcarshops.com/.

[pessemist]

Originally Posted by Luccia at Pelican Parts

Use this site to help you find a Porsche indy shop in your area: https://www.pcarshops.com/.

Thanks. But before I commit to a shop I'd rather investigate the issue myself. That's why I posted here--to try and get some insight into those codes and possible cures or diagnostic procedures I could do myself.

I have a friend coming over Friday and we are going to do a vacuum check. The other parts are probably due for replacement anyways.

Any other suggestions would be welcome.

Thanks!

[Luccia at Pelican Parts]

A vacuum leak is possible and a good place to check first before replacing parts. You can replace those parts as preventative, but definitely be sure to diagnose the issue. Doing a quick search on our forum, I found this thread where the individual has 3 of the codes you have: http://forums.pelicanparts.com/porsche-996-997-991-forum/930729-996-3-4-fault-codes-p1124-p1126.html. Not much, but some info for P0150 here: http://forums.pelicanparts.com/porsche-996-997-991-forum/930093-p0150-codes.html. Let us know what you guys find out.

[pessemist]

Originally Posted by Luccia at Pelican Parts

A vacuum leak is possible and a good place to check first before replacing parts. You can replace those parts as preventative, but definitely be sure to diagnose the issue. Doing a quick search on our forum, I found this thread where the individual has 3 of the codes you have: http://forums.pelicanparts.com/porsche-996-997-991-forum/930729-996-3-4-fault-codes-p1124-p1126.html. Not much, but some info for P0150 here: http://forums.pelicanparts.com/porsche-996-997-991-forum/930093-p0150-codes.html. Let us know what you guys find out.

Thanks guys! Looks like it turned out to be the Gas Cap gasket. It looked a little rough but after I replaced it, we are going on 300 miles without the dreaded CHECK SYSTEM light of death appearing. Hopefully, problem solved.