996 Turbo / GT2 Turbo discussion on previous model 2000-2005 Porsche 911 Twin Turbo and 911 GT2.

P1508 + P0492 codes...symptoms...opinions..any guess?

Thread Tools
 
Rate Thread
 
Old Nov 24, 2007 | 03:29 PM
  #1  
Pierre996TT's Avatar
Thread Starter
|
Registered User
Joined: May 2004
Posts: 1,035
From: Lo Barnechea & Viņa del Mar
Rep Power: 66
Pierre996TT has a spectacular aura aboutPierre996TT has a spectacular aura aboutPierre996TT has a spectacular aura about
Question P1508 + P0492 codes...symptoms...opinions..any guess?

Yesterday in traffic I got a PSM and ABS lights come on but went off after restart the car.

Today driving in canyons with a group of friends I loose all throttle and the dash beeps + displays Check Engine + Shutdown Consult Dealer immediately (or similar words). At this point I did pull over as there is no throttle, stop and the engine was running rough and full throttle gives you a 200 rpm increase and that's it. Ok then; turn it off, restart the car and all is well again with the CEL on and runs great. Then returning home the Check Engine light disappear and the car still running great but I did run durametric:



Motronic 7.8
Current Fault Codes


P0492 (yesterday on traffic)
Porsche fault code 208 - Secondary-air system bank 2



P1508 (today driving in canyons)
Porsche fault code 408 - Function monitoring
Torque comparison




For what I found:

P1508 Torque Comparison Function Monitor - Signal Implausible
Possible cause of fault
- MAF sensor faulty or at fault detection threshold
- DME control module faulty


I have OEM filter and AirBox, 30k milles, and I have never clean or touch the MAF.

Do these symptoms are a clear MAF failure or polluted?

Thanks!
 
Old Nov 24, 2007 | 03:50 PM
  #2  
Mikelly's Avatar
Registered User
Joined: Mar 2007
Posts: 3,813
From: Spotsylvania, Va
Rep Power: 322
Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !Mikelly Is a GOD !
I believe you have a bad mass air sensor.

I think I had this very issue back in July.
Mike
 
Old Nov 24, 2007 | 04:29 PM
  #3  
PorschePhd's Avatar
Registered User
Joined: Jul 2003
Posts: 3,670
Rep Power: 189
PorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond repute
Looks bad, without knowing what the voltage is at just "on" and at "idle" I would tell you to clean it, reset then see if it comes back. if it does then it is due for a MAF.
 
Old Nov 25, 2007 | 09:36 AM
  #4  
wirx's Avatar
Registered User
15 Year Member
Joined: Jan 2007
Posts: 301
From: Estonia (Europe)
Rep Power: 43
wirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud ofwirx has much to be proud of
Seems that MAF is bad, I have similar problems once - throtle respond only 200rpm and CEL too, after replacing MAF everything is fine.
 
Old Nov 25, 2007 | 07:18 PM
  #5  
Euclid's Avatar
Registered User
Joined: Oct 2007
Posts: 547
From: Austin, TX
Rep Power: 40
Euclid is infamous around these parts
I only get one, doesn't mention MAF:


Possible fault cause
  • DME control module faulty
 
Old Nov 25, 2007 | 07:57 PM
  #6  
Pierre996TT's Avatar
Thread Starter
|
Registered User
Joined: May 2004
Posts: 1,035
From: Lo Barnechea & Viņa del Mar
Rep Power: 66
Pierre996TT has a spectacular aura aboutPierre996TT has a spectacular aura aboutPierre996TT has a spectacular aura about
Arrow

Originally Posted by PorschePhd
Looks bad, without knowing what the voltage is at just "on" and at "idle" I would tell you to clean it, reset then see if it comes back. if it does then it is due for a MAF.
Thanks Stephen!

I did use Durametric after driving this afternoon, resetting up and I follow your instructions getting this actual values:




it seem OK because the actual values has to be 1.2 to 1.5 V at idle speed.

Then I did with the car stop but at different speeds:



Thus, with this values and the car running fine for now, should just clean it? or the MAF will die very soon?
 
Old Nov 25, 2007 | 08:01 PM
  #7  
PorschePhd's Avatar
Registered User
Joined: Jul 2003
Posts: 3,670
Rep Power: 189
PorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond reputePorschePhd has a reputation beyond repute
Yep, lets try cleaning it first.
 
Old Feb 24, 2009 | 08:32 AM
  #8  
Purplxd's Avatar
Registered User
Joined: Sep 2008
Posts: 942
From: Vancouver
Rep Power: 65
Purplxd has much to be proud ofPurplxd has much to be proud ofPurplxd has much to be proud ofPurplxd has much to be proud ofPurplxd has much to be proud ofPurplxd has much to be proud ofPurplxd has much to be proud ofPurplxd has much to be proud of
I know this is old.... but I just got this same code today and the same thing happened. Did you end up replacing it?

Cheers
Aaron
 
Old Apr 9, 2009 | 01:28 AM
  #9  
jeff4774's Avatar
Registered User
Joined: Mar 2008
Posts: 120
From: los angeles
Rep Power: 23
jeff4774 is infamous around these parts
can someone point me to where the MAF sensor is, and what i should use to clean it, and finally a price for the part if i need to replace it...not dealer price, aftermarket if avaliable.

thanks.
 
Old Apr 9, 2009 | 01:58 AM
  #10  
dixie's Avatar
Registered User
Joined: Nov 2005
Posts: 463
Rep Power: 44
dixie is a name known to alldixie is a name known to alldixie is a name known to alldixie is a name known to alldixie is a name known to alldixie is a name known to all
Maf is just behind the air filter,you can easily screw it out and clean it with CRC maf cleaner.
 
Old Apr 9, 2009 | 07:00 AM
  #11  
wross996TT's Avatar
Registered User
Joined: Feb 2005
Posts: 4,660
Rep Power: 254
wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !wross996TT Is a GOD !
a pic for you
 

Last edited by wross996TT; May 23, 2016 at 11:47 AM.
Old Apr 9, 2009 | 10:58 AM
  #12  
jeff4774's Avatar
Registered User
Joined: Mar 2008
Posts: 120
From: los angeles
Rep Power: 23
jeff4774 is infamous around these parts
Awesome! Thanks for the illustration!
 
Old Apr 9, 2009 | 02:19 PM
  #13  
PeterK's Avatar
Registered User
Joined: Feb 2007
Posts: 389
From: san antonio, tx
Rep Power: 35
PeterK is infamous around these parts
Let us know whether that fixed your problem or not.
 
Old May 15, 2009 | 07:55 PM
  #14  
jeff4774's Avatar
Registered User
Joined: Mar 2008
Posts: 120
From: los angeles
Rep Power: 23
jeff4774 is infamous around these parts
update,
cleaned it,
problem persists.
time to replace MAF?
whats the best place to get one?
 
Old Jun 9, 2009 | 10:38 AM
  #15  
vbmw335's Avatar
Registered User
Joined: Dec 2007
Posts: 1,215
From: Socal
Rep Power: 82
vbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant futurevbmw335 has a brilliant future
To the OP what was this problem? was it MAF?
 


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -6. The time now is 12:19 PM.