Buick When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

03 Regal runs good with MAF unplugged

Thread Tools
 
Search this Thread
 
Old 08-25-2012, 11:21 PM
  #1  
Junior Member
Thread Starter
 
stuartsx5's Avatar
 
Join Date: Aug 2012
Location: Marshfield, MO
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
stuartsx5 is on a distinguished road
Default 03 Regal runs good with MAF unplugged

I have a 2003 Buick Regal that my daughter drives. Monday she put gas in it and Wednesday it died in rush hour. Seemed like it was starving for gas so changed the TPS on some advice, no luck. Changed the fuel filter, ran for about two miles, died at an idle then wouldn't start. Under the wrong advice from the local parts store changed the fuel pump because it showed 50 psi and they told me it should be 85 psi (they were wrong). Went to load it on a trailer to haul it home and on a whim I unplugged the MAF sensor and it ran fine. Drove it the eight miles home, plugged in the MAF sensor and it loaded up with gas and died. Cleaned with MAF sensor cleaner, no luck. The only time it throws a code is when it is running and I plug the MAF in (low voltage). No codes when MAF is unplugged. About everything I have read says the MAF is bad. I understand that by uplugging the MAF I am bypassing some other important readings such as O2 sensors. Should I look at something else or bite the bullet and replace the MAF? Any help is greatly appreciated as I am not a mechanic. We are $360 dollars into this and it still is not fixed.
Old 08-26-2012, 04:19 AM
  #2  
Retired



Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Dark Side, AZ
Posts: 17,920
Received 1,780 Likes on 1,304 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

If it runs fine unpugged, then its the classic MAF failure. But not a complete failure. It'* still sending a signal to the PCM but very different from normal, so the PCM thinks its working fine.
And no, it doesn't bypass the O2 sensor. The PCM just uses a predertimined set of values based on cylinder air mass volume. Its like a fall back.

So yea, get a new one.
__________________
Retired Administrator
2002 *-10 5.7 V8
2023 Jeep Rubicon Diesel

Old 08-26-2012, 04:46 AM
  #3  
Junior Member
Thread Starter
 
stuartsx5's Avatar
 
Join Date: Aug 2012
Location: Marshfield, MO
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
stuartsx5 is on a distinguished road
Default

Thanks for the reply Mike. I will grab one tomorrow and see how it does. Do I need to do anything to reprogram my computer after installing the new MAF?
Old 08-26-2012, 05:28 AM
  #4  
Retired



Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Dark Side, AZ
Posts: 17,920
Received 1,780 Likes on 1,304 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

No sir. Plug-n-Play.
__________________
Retired Administrator
2002 *-10 5.7 V8
2023 Jeep Rubicon Diesel

Old 08-31-2012, 03:31 PM
  #5  
Junior Member
Thread Starter
 
stuartsx5's Avatar
 
Join Date: Aug 2012
Location: Marshfield, MO
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
stuartsx5 is on a distinguished road
Default

Just wanted to touch base and say thanks again. The problem wound up being the MAF sensor [I]and[I] the connector or wires. I finally took it to a mechanic he determined the problem and fixed it.
Old 09-16-2012, 08:29 PM
  #6  
Senior Member
Posts like a Turbo
 
Shaun_300's Avatar
 
Join Date: Feb 2012
Location: Ottawa, Ontario
Posts: 308
Likes: 0
Received 1 Like on 1 Post
Shaun_300 is on a distinguished road
Default

Good to hear you got it fixed up! Those 3800'* are notorious for MAF sensor failures.
Old 09-16-2012, 11:09 PM
  #7  
Junior Member
Thread Starter
 
stuartsx5's Avatar
 
Join Date: Aug 2012
Location: Marshfield, MO
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
stuartsx5 is on a distinguished road
Default

Well....the problem isn't resolved. After getting it back, the check engine light is on. Now it is throwing the P0420 catylitic system bank one below thresh hold. We have replaced the upstream O2 sensor cause the mechanic doesn't think the convertor is bad. The light still comes on. I don't know what the next step is.
Old 09-16-2012, 11:32 PM
  #8  
Senior Member
Certified GM nut
 
SignOfZeta's Avatar
 
Join Date: Mar 2005
Location: New Milford, CT
Posts: 2,284
Received 17 Likes on 14 Posts
SignOfZeta has a spectacular aura aboutSignOfZeta has a spectacular aura about
Default

Originally Posted by stuartsx5
Well....the problem isn't resolved. After getting it back, the check engine light is on. Now it is throwing the P0420 catylitic system bank one below thresh hold. We have replaced the upstream O2 sensor cause the mechanic doesn't think the convertor is bad. The light still comes on. I don't know what the next step is.
It'* always good to replace the upstream sensor, but try replacing the downstream O2 sensor before you declare the catalytic converter bad.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
nick52405
Buick
10
05-12-2011 10:45 PM
racer42
General GM Chat
3
03-04-2011 12:13 AM
trixster68
1992-1999
5
08-03-2009 09:57 AM
Hans
1992-1999
14
07-11-2005 09:56 PM
Logan
General GM Chat
7
11-03-2004 10:55 PM



Quick Reply: 03 Regal runs good with MAF unplugged



All times are GMT -4. The time now is 05:14 PM.