HkPlinker

Ok, engine light came on a few days ago, called wrench buddy and took the 997.1 TT to ORiley's and plugged the car in as suggested. Readout P2190 Too rich at idle Bank II.

Took the car to Porsche and Plugged in and read everything's normal, no ill readings, dropped in a new air filter reset the light.
and sent me on my way.

150 miles later, BAM, engine light on, and again P2190.

Car runs great, called dealer they said could be a O2 sensor or even the catalysts (which are under warrantee) .

Any thoughts (to a two week old owner) ?

Igooz

I Googled it for you: CP2190 Lambda control adaptation FRAU (lower load range) - below limit value Possible causes: - Incorrect main filling signal from hot-film mass air flow meter - Fuel pressure too high - Injection valve faulty (dripping) - Tank vent faulty (does not close completely)

The codes above read to me like OBD stuff.
Sounds like the dealer is not too worried?

neanicu

You have to look at Live data and see the fuel trims and what the O2s are doing. If the O2s are showing a rich condition but are responding to TPS inputs and are switching within stoichiometric I wouldn't call the O2s as faulty.
What can happen is you have a vacuum leak and the computer is trying to adjust air/fuel ratio by dumping too much fuel to compensate for the extra air and the O2s are picking that. Or your MAF could be giving the computer a false reading.
Lastly,I wouldn't rule out a clogged exhaust due to a melted cat because of the car running rich for a while.

Good luck!

HkPlinker

Well, during the "live data" readings with the car at idle and plugged in at the Porsche dealer, he was not alarmed at all. Said everything's within normal readings and suggested a new air filter.

Now tonight (six days later),
I started the car today after two days of rest and upon start up there was a "gargly" rattling from underneath and deep (rich) smell from the exhaust, or at least that is where I believed the rumble started from right at a the cold start up.
I let the car run for 20-30 seconds and shut it off and restarted a couple of times and I could not replicate the sound. Also, after a couple of errands (stops and restarts) the gargle never came back.
It didn't sound like rocks rattling around like my wife's Mercedes E class when one of her Cats failed and was replaced. It was more like a loud rattle and stopped once the car was at normal idle.

I assume it's back to the dealership, unfortunately it's 75 miles away.

Macster

As is often the case the problem is intermittent and will remain so for some time.

The engine has rich running bank. The "rich" smell is a clue, as is the "rumble". This is exhaust backfires which is a sign of rich running.

Given the symptoms are confined to one bank the problem probably lies with something confined to that bank, with one possible exception. A failure limited to just the bad bank would be one or more leaking injectors. The exception I mentioned above? The MAF.

I actually like the MAF as the source of the problem more than the leaking injector possibility.

An intermittent problem is more often in an electrical device like a MAF than it is in an electrical/mechanical device like the injector.

As you have observed from the symptoms and trying to reproduce the symptoms is the MAF if is the culprit will only manifest abnormal readings for a short period of time. Shutting off the engine then restarting it will almost always meet with failure to reproduce the symptoms as this cutting of power "resets" the MAF.

As long as the noises are not of the scary type which could be an early warning of pending serious internal engine trouble and you feel comfortable running the engine, one thing you can consider is disconnecting the MAF and seeing if the behavior still occurs.

Be sure you rid yourself of any static electricity before touching the MAF and its wiring cable and the harness.

Ideally once you have disconnected the MAF you clear DTC error codes, even if there aren't any to simply reset the learned fuel trims back to their defaults, among other things. Then as close to the conditions before when the symptoms were present repeat your tests and see if the symptoms appear.

Keep in mind with the MAF disconnected the CEL may come on, or possibly even other warnings might appear. The MAF signal is used by other system controllers in the car like PSM and ABS. If this signal is absent or implausible these controllers can flag a problem.

If the symptoms stay away and you are sure you duplicated the conditions under which they appeared before then reconnect the MAF, clear the codes again, and retest to confirm the symptoms reappear.

If the symptoms appear with the MAF disconnected then reconnect the MAF, and clear the codes and consider taking the car to the dealer. Testing for leaking injectors or other things is often something best left to the professional tech.

GTRNICK

Check the O2 sensors the washers around them might be worn away and might be sitting loose. For me I changed all of the and the problem went away. I also changed the MAFs too but first tried cleaning them.

HkPlinker

OK, So I am trying to clean my MAFs. The driver listed to remove the sensor is a T25 "Security" tamper proof, however none of my T25, or T20, or T27 or any tamper proof TORX will fit this screw head.

Am I missing something here ?

neanicu

Yes,you're missing a tamper proof socket,which is a T25 with a hole in the middle.

HkPlinker

I just figured it out. I need a five point tamper proof Torx not a standard six point tamper proof. and No one in town is open now . . .

drh

In my experience the car will stumble upon acceleration when the MAF is going **** up.

neanicu

Yes,that's what I said...

HkPlinker

neanicu, You are incorrect. This IS what I have. That is a SIX point Torx Plus (tamper proof). It requires a FIVE point Torx (tamper proof)

neanicu

Ok,got it. Didn't know they make 5 point too... I just thought you don't have tamper proof and it doesn't fit over the notch in the middle...
Anyway...you might try with what you have...that bolt shouldn't be crazy tight...

HkPlinker

I tried a few times and it keeps scratching the screw head . . . I'm bummed. I was all set for an easy DIY and I got nothing to show for it . . . .

The search continues in the morning . . .

neanicu

Just a suggestion before you call it quits,you can try spinning it out using needle nose pliers or snap ring pliers...if you have them...
Just grab 2 corners opposite to each other and spin.