|
|
|
|
Thread Tools | Display Modes |
06-12-2004, 06:17 PM | #1 |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
Cobb Stage 2 running very lean
So I installed Stage 2 with the AP a couple weeks ago, put it on the dyno today, got very good numbers, BUT running very lean. The guy that was running the dyno said, I should be very worried about it. Now, I don't know much about this stuff, but it got me worried. The tech suggested that I call Cobb and ask them about it, which I'm going to do on Monday.
I'm wondering if anyone else has this problem and if this could cause damage. I'll post the update after I talk to Cobb. Thanks
* Registered users of the site do not see these ads.
|
06-12-2004, 06:26 PM | #2 |
Scooby Newbie
Member#: 62870
Join Date: May 2004
|
Do you by chance have an intake
|
06-12-2004, 06:31 PM | #3 | |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
Quote:
|
|
06-12-2004, 06:50 PM | #4 |
Scooby Specialist
Member#: 18709
Join Date: May 2002
|
what are your EGT's?
|
06-12-2004, 07:03 PM | #5 | |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
Quote:
|
|
06-12-2004, 07:37 PM | #6 |
Scooby Specialist
Member#: 15059
Join Date: Feb 2002
Chapter/Region:
MAIC
Location: Latrobe, PA
Vehicle:2004 WRX STi 1991 TSi |
Do you have actual proof of running lean? Any a/f numbers?
If not, might wanna snag them from the dyno guy. I doubt Cobb will be able to do anything for you without some numbers. |
06-12-2004, 07:39 PM | #7 | |
Scooby Specialist
Member#: 18709
Join Date: May 2002
|
Quote:
Last edited by clamdip; 06-12-2004 at 07:45 PM. |
|
06-12-2004, 07:48 PM | #8 |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
I have the print of the graph here. I'm getting around 15.1 A/F at full boost. It doesn't get more gas untill around 5200 RPM. From around 2500 RPM untill 5200 RPM it's running at 14.5 and higher. The guy at the dyno place told me this is very lean. I've been reading the cobb forum and it seem like people were complaining that they were running too lean and they were getting 12A/F. I'm getting more than that, and I'm getting very worried.
Any ideas guys? |
06-12-2004, 08:15 PM | #9 |
Scooby Specialist
Member#: 18709
Join Date: May 2002
|
okay, here is a good write up straight from Trey.
http://www.wrxforum.com/cgi-bin/ulti...3;t=004269;p=3 here is the full thread: http://www.wrxforum.com/cgi-bin/ulti...=004269#000001 hope this helps. this seems to be what you're experiencing. i don't think you have to worry. seems scary though huh? i think that the guys at cobb are very experienced and know a whole lot of what they're doing. however, if you still have questions and still are a bit worried, then you should give them a call. however, after i read this when i first got my stage 2, i wasn't worried. i guess you could say that i put my faith in Cobb. |
06-12-2004, 09:58 PM | #10 |
Scooby Specialist
Member#: 3841
Join Date: Jan 2001
Location: Sacramento, CA
Vehicle:2004 WRX Wagon UTEC+VF22+WI |
You can argue about how safe it is, and I don't think Cobb's supporters will ever let someone say they did something less than perfect, however safety or not you'd be leaving power on the table with those fuel ratios. However, I can't believe it's that lean and not melted into a puddle. You should investigate the shop's O2 sensor hookup being proper, more so than just asking them. Most likely it's just bad data. Do you possibly have an exhaust leak?
|
06-12-2004, 10:02 PM | #11 | |
Scooby Specialist
Member#: 18709
Join Date: May 2002
|
Quote:
|
|
06-13-2004, 09:10 AM | #12 |
Scooby Specialist
Member#: 20442
Join Date: Jun 2002
Chapter/Region:
NESIC
Location: Chelmsford, MA
Vehicle:2022 WRX Limited WRB |
I'd have to agree on the bad data as well. If you were really running 15:1 A/F at full boost, your engine would already be toast by now. That's too lean for an N/A motor at full throttle and just insane for a forced induction motor.
|
06-13-2004, 04:30 PM | #13 | |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
Quote:
If the engine starts overheating because it's running lean, will I be able to see it on the temp gauge or do I need to have an EGT gauge? Also, is there another way of checking A/F, other than dyno? Last edited by grozgon; 06-13-2004 at 04:36 PM. |
|
06-13-2004, 04:59 PM | #14 |
Scooby Specialist
Member#: 3841
Join Date: Jan 2001
Location: Sacramento, CA
Vehicle:2004 WRX Wagon UTEC+VF22+WI |
The engine overheating is not the problem- it's detonation and poor performance you'd see from air/fuel ratios like that. Since you're not complaining of those symptoms, it's hard to believe you're really running that lean. Again, check for exhaust leaks.
You can monitor AFR yourself with one of the many available wideband O2 sensor setups. The TXS Tuner is a nice one with lots of features but expensive. I use an LM-1 from innovatemotorsports.com. |
06-13-2004, 09:49 PM | #15 | |
Scooby Specialist
Member#: 23145
Join Date: Aug 2002
Location: soCal sux
Vehicle:2004 WRX STi BLUE |
Re: Cobb Stage 2 running very lean
Quote:
Im curious man! |
|
06-14-2004, 12:38 AM | #16 | |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
Re: Re: Cobb Stage 2 running very lean
Quote:
|
|
06-14-2004, 12:47 AM | #17 |
Scooby Specialist
Member#: 23145
Join Date: Aug 2002
Location: soCal sux
Vehicle:2004 WRX STi BLUE |
good #s |
06-14-2004, 01:01 AM | #18 |
Former Vendor
Member#: 26933
Join Date: Oct 2002
Chapter/Region:
BAIC
Location: Fairfield, CA
Vehicle:2006 STI CGM |
yep.. 221 is right about where it should be. Aside from the peak numbers, did the curve look smooth? If so, then I'd say there is no way you could have been running that lean.
-- Ed |
06-14-2004, 01:26 AM | #19 |
Scooby Newbie
Member#: 55101
Join Date: Feb 2004
Location: CT, U.S.A.
Vehicle:2004 STI Blue |
Macabre,
I recognize you from VW boards in the past. Is there anyway to pull a/f ratio from the car's ECU, like I seem to remember you could with the Vag Com?? is A/F ration part of the OBD II standard or an extended function? Don |
06-14-2004, 02:08 AM | #20 |
Former Vendor
Member#: 26933
Join Date: Oct 2002
Chapter/Region:
BAIC
Location: Fairfield, CA
Vehicle:2006 STI CGM |
More veedub guys? I was on vwvortex.com as well. You can pull a/f ratio using deltadash or any universal OBD-II logger, I believe. The problem is that the stock "wideband" O2 sensor on the suby is only accurate down to ~11.5:1.
-- Ed |
06-14-2004, 03:11 AM | #21 |
Scooby Specialist
Member#: 3841
Join Date: Jan 2001
Location: Sacramento, CA
Vehicle:2004 WRX Wagon UTEC+VF22+WI |
The UTEC doesn't even consider it accurate that far down. And it's probably not terribly precise or responsive anywhere.
Anywho, standard OBDII scanners will not give you a reading from the stock front sensor. You'd need a deltadash to get that, for whatever good it will do you. If you're going to be tuning you should just bite the bullet and get a wideband setup. |
06-14-2004, 02:48 PM | #22 | |
Scooby Newbie
Member#: 48109
Join Date: Nov 2003
Location: Maple Shade, NJ
Vehicle:2004 Subaru WRX Silver |
Quote:
|
|
06-14-2004, 04:40 PM | #23 |
Scooby Guru
Member#: 8785
Join Date: Jul 2001
Chapter/Region:
SWIC
Vehicle:02 c_turner@ix. netcom.com |
I have now seen this over 6 times with the Cobb flash. I sent emails and spoke with Trey about it so he would know what I was seeing. There must be an odd problem in the calibration of the ECU. I believe him when he says he tunes for XX AFR and that his car/cars are showing that on his dyno.. But for some reason cars in other states (maybe altitude) are running lean AFR's. I had one car run at 12.5 to 1 almost across the board and a few I saw in the 13's and just let out of the gas on the dyno.. No point in potentialy hurting something. I did have one that ran near 11 to 1 and made good power.. So its not ALL Cobb ECu'[s on ALL cars..
Better Call Trey and fax him those charts.. You might have an issue with your fuel system or maybe an MAF leak or you might have an issue with the flash. C |
06-14-2004, 04:44 PM | #24 | |
Former Vendor
Member#: 26933
Join Date: Oct 2002
Chapter/Region:
BAIC
Location: Fairfield, CA
Vehicle:2006 STI CGM |
Quote:
-- Ed |
|
06-14-2004, 05:03 PM | #25 |
Scooby Specialist
Member#: 33410
Join Date: Feb 2003
Chapter/Region:
Tri-State
Location: wishing i was somewhere else
Vehicle:08 wrx dgm |
i'd post in your regional forum to see if anyone in your area has a delta dash that can help you. although its not accurate below 12:1 or so... you'll still be able to see if at say 4800rpm you're running 15:1 or if the graph bottoms out. it's better than nothing.
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Cobb Stage 2 Lean | rhurley13 | AccessPort | 6 | 04-22-2010 07:32 PM |
Cobb Stage 2 Running Safely? | bmw50021 | AccessPort | 3 | 11-22-2006 08:20 PM |
Cobb stage 2 running lean. | 06rexwagon | AccessPort | 2 | 07-12-2006 12:04 AM |
STi Cobb stage 2 running rich or lean? | SubaruBen | Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) | 8 | 10-14-2005 12:48 PM |
my cobb stage 2 running lean!!! | swol3 | Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) | 17 | 09-18-2004 07:55 AM |