Page 1 of 2 12 LastLast
Results 1 to 20 of 37

Lean Air bank 1 and 2 codes (P0171, P0151)

This is a discussion on Lean Air bank 1 and 2 codes (P0171, P0151) within the General Help forums, part of the LSx Technical Help Section category; About 4 weeks ago my A4 98 'maro took 2 good cranks to start and once it did it was ...

  1. #1
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    Lean Air bank 1 and 2 codes (P0171, P0151)

    About 4 weeks ago my A4 98 'maro took 2 good cranks to start and once it did it was in limp mode with a MIL. I blamed it on the girlfriend after hearing that she put 87 in the tank (it normally gets 93). After two tanks of 93 failed to fix the problem, I took it to Advanced to get the MIL checked out, The codes were: P0131, P0137, P0151, and P0157. Low volts on all oxygen sensors. I assumed it needed new sensors bc the car was at 55,000 and had never had new ones. So I bought 4 boschs and swapped them in on Saturday. After getting the MIL cleared the car started well and ran well until i took it on the highway and romped on it. It throws the MIL as soon as I go WOT and returns to limp mode. I checked the codes again and they read P0131 and P0151. After researching the codes I found that they correspond to a lean air problem. I then checked the MAF and TB for anything and they were clean. Also a visual inspection for vacuum leaks didn't show any bad/cracked hoses. Any opinions would be greatly appreciated.

    For reference: GM replaced my fuel pump and filter @ 52,300 last Oct. That's the last service beside the new sensors and regular oil changes. I also have a K&N ram air kit.
    Last edited by MeanGreen98; 05-24-2010 at 08:26 PM.

  2. #2
    Moderator 35th-ANV-SS's Avatar
    Join Date
    Oct 2008
    Location
    Wherever life takes me
    Posts
    12,465

    Red
    02 35th LE Camaro SS

    You mentioned you checked the MAF and it looked clean. Did you physically clean it? Running lean on both banks is either a) vacuum leak or b) dirty/faulty MAF sensor I would think.

    A MAF can "look" clean and actually be dirty. I would spend the $6 and buy a can of CRC MAF cleaner found at any autoparts store and start with that to at least eliminate the possibility of it being the MAF.

  3. #3
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    I visually inspected the MAF i.e. I didn't spray it. A friend mentioned the cleaner, I will get some tomorrow.

  4. #4
    Moderator Cutlass's Avatar
    Join Date
    Apr 2008
    Location
    Madison, WI
    Posts
    6,998

    1999 Formula WS6 M6-sold
    2001 Silverado Z71

    Low fuel pressure can also cause a lean condition. Shouldn't be a problem for you considering your recent fuel pump and filter change, but you should check the pressure anyways.
    Is this a stock, unmodified GM MAF sensor?
    I think cleaning it with CRC MAF cleaner is a good idea especially with a K&N filter. Sometimes the oil on those filters comes off and coats the sensor and skews its readings

  5. #5
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    This is a stock MAF, I'm worried that there is an underlying problem that ruined my stock fuel pump and is now causing more problems.

  6. #6
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    I should pull out the MAF and spray it down right? Not just undo one side and spray the s#!% out of it?

  7. #7
    Moderator 35th-ANV-SS's Avatar
    Join Date
    Oct 2008
    Location
    Wherever life takes me
    Posts
    12,465

    Red
    02 35th LE Camaro SS

    Quote Originally Posted by MeanGreen98 View Post
    I should pull out the MAF and spray it down right? Not just undo one side and spray the s#!% out of it?
    I completely removed mine when i cleaned it. I believe it states this in the directions on the can also. Unplug it and take it out and spray the &^%$ out of it. be sure to fully let it dry before hooking it back up.

  8. #8
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    10-4. What about the pcv? I've had people at work mention that as well. Can the ball inside that just be stuck too? If it is, brake cleaner would loosen that up?

  9. #9
    Moderator 35th-ANV-SS's Avatar
    Join Date
    Oct 2008
    Location
    Wherever life takes me
    Posts
    12,465

    Red
    02 35th LE Camaro SS

    Quote Originally Posted by MeanGreen98 View Post
    10-4. What about the pcv? I've had people at work mention that as well. Can the ball inside that just be stuck too? If it is, brake cleaner would loosen that up?
    If you take it off and can hear the ball moving freely I would say you are fine. If not, you can try cleaning it, but depending on price I would replace it.

    Your symptoms really do sound like a MAF problem to me though. lean on both banks is usually an air leak or MAF faulty reading, causing the computer to either retard fuel or dump more fuel into the mix than is needed...causing a lean or rich condition.

    In your case, which is lean, this is the worse of the two. You do not want to be running your car lean. It can lead to major problems if not fixed properly.

  10. #10
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    Major problems? I.e. detonation or other things? Doesn't limp mode keep me from exploding it?
    Last edited by MeanGreen98; 05-24-2010 at 10:19 PM.

  11. #11
    Moderator 35th-ANV-SS's Avatar
    Join Date
    Oct 2008
    Location
    Wherever life takes me
    Posts
    12,465

    Red
    02 35th LE Camaro SS

    Quote Originally Posted by MeanGreen98 View Post
    Major problems? I.e....
    Running lean makes the engine run hot. This tends to lead to pinging/knocking, or pre-ignition. This causes greatly increased cylinder pressures and heat, and can damage internal engine components like bearings, piston rings/ring lands, burn pistons and valves, bend/break rods, etc...

  12. #12
    Member 383ls6's Avatar
    Join Date
    Nov 2009
    Location
    dallas,texas
    Posts
    158

    red
    2002 z/28

    do you have access to a scanner that will allow you to read live data(fuel trims,MAF gps)?

  13. #13
    Member rkvette's Avatar
    Join Date
    Apr 2010
    Location
    northeastern pa.
    Posts
    175

    victory red
    2007 zo6

    i had somthing like that happen to me on my 2002 covette conv... i bought a hand held tuner, try to get a couple more horses... i thought i did a good job ,but did not !! vette stared to miss at low speeds and turned a light on.?. went to my friendly gm dealer and they found couple bad spark plugs, car had only 1,200 miles.. i put in tune,, too lean !! melted couple plugs they replaced all n/c., no problem- never try that again, vette went down strip 7 tens quicker with right drag tires,mid to low 13 seconds when i got out of the hole,right and good shifts on the 6 speed, got into 4 th just before finish..rkvette

  14. #14
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    Much to my delight, when I purchased a can of MAF cleaner from Advance I got a can of TB cleaner free. After spraying them both down, I took the car out and did notice a slight SOP difference but the car is still in nanny mode. I'm gonna go back out in a few minutes and see if the car starts on one crank.

    *It didn't.
    Last edited by MeanGreen98; 05-25-2010 at 05:36 PM. Reason: update

  15. #15
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    Quote Originally Posted by 383ls6 View Post
    do you have access to a scanner that will allow you to read live data(fuel trims,MAF gps)?
    I do not. A friend may be passing by me on his way to Parkersburg this weekend, hopefully he'll bring his scanner and stop by.

  16. #16
    Veteran 0rion's Avatar
    Join Date
    Aug 2005
    Location
    ohio
    Posts
    22,520

    98 Formula
    06 duramax

    check your fuel pressure....also, check the back of the pcv hose where it bends to go into the intake. Those like to crack there. Replacing the fuel pump with a stock pump was a bad idea...probably pretty expensive too. How many miles are on that pump? It could also be a cracked hose in the tank that goes to the pump.....that's not unheard of either. First step is to check your fuel pressure. The not cranking on the first crank makes me believe it's pump/pressure related.

  17. #17
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    Quote Originally Posted by 0rion View Post
    how many miles are on that pump?
    ~1500

  18. #18
    Junior Member MeanGreen98's Avatar
    Join Date
    May 2010
    Location
    Martinsburg,WV
    Posts
    45

    Med. Green Metallic
    1998 Camaro

    Since my friend canceled his trip I was forced to go out and buy a fuel pressure tester. I found out that at idle the car hovers at ~33 psi. When I move the throttle the pressure drops slightly and never makes it to 50. So I'm quite confident it's a fuel problem. I'm ruling out the pump and filter for now b/c they are pretty freakin new, (less than 2,000 mi), and they are bonafide parts from the general. What about the fuel damper?

  19. #19
    Moderator Cutlass's Avatar
    Join Date
    Apr 2008
    Location
    Madison, WI
    Posts
    6,998

    1999 Formula WS6 M6-sold
    2001 Silverado Z71

    No I don't think the damper would do that. Its gotta be the pump or the filter. Unless you got a bad fuel pressure gauge...unlikely.

  20. #20
    Veteran 0rion's Avatar
    Join Date
    Aug 2005
    Location
    ohio
    Posts
    22,520

    98 Formula
    06 duramax

    Quote Originally Posted by MeanGreen98 View Post
    Since my friend canceled his trip I was forced to go out and buy a fuel pressure tester. I found out that at idle the car hovers at ~33 psi. When I move the throttle the pressure drops slightly and never makes it to 50. So I'm quite confident it's a fuel problem. I'm ruling out the pump and filter for now b/c they are pretty freakin new, (less than 2,000 mi), and they are bonafide parts from the general. What about the fuel damper?
    other than the fuel pump/filter about the only other option you have is a split hose in the tank. Definitely pump related IMO.

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Need help with lean codes bank 1&2
    By Ieatstangs in forum General Help
    Replies: 14
    Last Post: 05-13-2012, 08:28 PM
  2. Help: ls1 codes P0131 p0137 p0151 p0157 help please
    By skinypuppy in forum General Help
    Replies: 37
    Last Post: 06-16-2011, 03:09 PM
  3. Throwing codes for bank 1 and 2 being lean.
    By !!!FAST!!! in forum External Engine
    Replies: 2
    Last Post: 08-14-2010, 07:06 AM
  4. Throwing Too Lean code P0171
    By !!!FAST!!! in forum General Help
    Replies: 6
    Last Post: 09-09-2009, 06:48 AM
  5. Throwing codes P0151 and P1153
    By 01ws6er in forum General Help
    Replies: 8
    Last Post: 08-13-2008, 09:31 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •