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

2001 GP runs only when MAF sensor is unplugged

Old 11-22-2016, 03:23 PM
  #1  
Junior Member
Posts like a V-Tak
Thread Starter
 
hoarybat's Avatar
 
Join Date: May 2015
Posts: 26
Likes: 0
Received 1 Like on 1 Post
hoarybat is on a distinguished road
Default 2001 GP runs only when MAF sensor is unplugged

Hi all. Symptoms:

A week ago the engine/car would abruptly stall after warmup leaving us stranded.
Got car home. Started it up idling the next day and within a few minutes it stalled. Attempting immediate restart would not work. Had to let car rest for an hour or so and then it would start and do the same stall again.

I then unplugged the MAF sensor and the car would remain running just fine with a very slight fluctuation on the RPMS negligible. At least it runs and won't stall or shut down at all and starts fine the next attempt too.

Googling I found the stalling when warm is or could be a CRANKSHAFT SENSOR GOING BAD. When to NAPA USED OBDII code reader, cleared the codes with MAF P0102 error. But that is because it was unplugged when I ran the test. Car will no longer even cold start now with it in.

No $$ to take car to the guys who has the big test machine $$ which tells you the exact problem. MAF problem Crankshaft sensor problem? dunno. Saw MAF sensor on ebay for $20 maybe I could try that? Any help appreciated.
Old 11-22-2016, 04:35 PM
  #2  
Senior Member
True Car Nut
 
2kg4u's Avatar
 
Join Date: Sep 2006
Location: Windsor, Ontario / Detroit, Michigan
Posts: 4,816
Received 241 Likes on 198 Posts
2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of
Default

If the car runs better when you unplug the MAF, the problem is the MAF. Pull it out and examine the fine wire elements. If one is broken you need a new MAF. If they are dirty you might be able to get away with cleaning them. If you try to clean them, do not use anything other than a spray for cleaning MAF'*. CRC makes a good one. Do not use carb cleaner or anything other than a cleaner specifically for MAF'*, and don't use anything that actually contacts the wires (like a Q tip).


Clean MAF element wires will be a nice shiny silver color.


Now the bad news. A decent MAF will run you at least $100. A MAF off Ebay for $20 is garbage. Hopefully a good cleaning will fix the issue.

Last edited by 2kg4u; 11-22-2016 at 04:38 PM.
Old 11-22-2016, 05:00 PM
  #3  
Junior Member
Posts like a V-Tak
Thread Starter
 
hoarybat's Avatar
 
Join Date: May 2015
Posts: 26
Likes: 0
Received 1 Like on 1 Post
hoarybat is on a distinguished road
Default

OK thanks I'll get some CRC MAF cleaner tomorrow. After letting the car cool for a few hours I actually was able to start the car idled ruff at low rpm smoothly at higher and after 1 minute the car shut off/stalled. I'll try the cleaner and get back and take photos of it as well maybe that will help thanks SOOO much sir.
Old 11-24-2016, 09:52 PM
  #4  
Junior Member
Posts like a V-Tak
Thread Starter
 
hoarybat's Avatar
 
Join Date: May 2015
Posts: 26
Likes: 0
Received 1 Like on 1 Post
hoarybat is on a distinguished road
Default

No pics but I did clean the sensor with CRC with no luck. The car runs with MAF unplugged doesn't run with it in. Thanks again I may get one from a junkyard as they said $30 as I can't dump $100 for that sensor into this car. Thanks again
Old 11-25-2016, 12:47 AM
  #5  
Senior Member
Posts like a Turbo
 
Mad_Coachman's Avatar
 
Join Date: Dec 2003
Location: Baldwin,New York
Posts: 245
Received 39 Likes on 29 Posts
Mad_Coachman will become famous soon enoughMad_Coachman will become famous soon enough
Default

Originally Posted by hoarybat
No pics but I did clean the sensor with CRC with no luck. The car runs with MAF unplugged doesn't run with it in. Thanks again I may get one from a junkyard as they said $30 as I can't dump $100 for that sensor into this car. Thanks again
The reason 2kg4u warned you against the cheap Ebay sensors because they are manufactured with cheap resistors that will throw your fuel trims way out of whack. I speak from experience on this. I found an OEM(Hitachi) MAF on Ebay from a junkyard for 25 bucks and it worked just fine.
Old 11-26-2016, 03:47 AM
  #6  
Junior Member
 
matt08a's Avatar
 
Join Date: Nov 2016
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
matt08a is on a distinguished road
Default Vacuum leak?

Most of the vehicles I come across like this, if the MAF sensor is not the problem, tend to have a vacuum leak. The MAF sensor tells the computer how much are is being used, so a vacuum leak will be unmetered and cause stalling and rough running, especially at low rpm. Try revving the engine and seeing if it runs better at high rpm. unplugging the MAF means the computer will have to figure that out on its own and vacuum leaks are not as noticeable anymore. Always a good place to start with symptoms like that. Try dumping some water around the engine bay and listen for the sound of the engine sucking it up. visually inspect any accessible vacuum lines for cracks and that they haven't popped off. You could pump smoke into a line and look for it coming back out somewhere as well. A cigar is sometimes a usable alternative to a real smoke machine.

--
Matt
Old 12-11-2016, 08:59 PM
  #7  
Junior Member
Posts like a V-Tak
Thread Starter
 
hoarybat's Avatar
 
Join Date: May 2015
Posts: 26
Likes: 0
Received 1 Like on 1 Post
hoarybat is on a distinguished road
Default

Hi all sorry it took so long on feedback. got an MAF from junkyard plugged it in car did not stall when up to temperature. Check engine did not clear so I disconnected battery to clear it and it has not come back on. Idle is still a little high when car is first started does better after a few minutes of running. I took out the ICV and it was all coated with black with much carbon. Didn't look good at all of course after 16 years. Don't know why it is not throwing a code. Either way car is running and hopefully will get us to springtime. Thanks....
Old 12-30-2016, 01:23 PM
  #8  
Junior Member
Posts like a V-Tak
Thread Starter
 
hoarybat's Avatar
 
Join Date: May 2015
Posts: 26
Likes: 0
Received 1 Like on 1 Post
hoarybat is on a distinguished road
Default

When I put the replacement Idle Control valve it gave me a service engine and would not clear after I disconnected battery to do so. Car is running smoothly tho and grandfathered for inspection so no biggie.....
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
200VEGAS
Chevrolet
8
02-14-2013 04:02 PM
stuartsx5
Buick
7
09-16-2012 11:32 PM
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


Thread Tools
Search this Thread
Quick Reply: 2001 GP runs only when MAF sensor is unplugged



All times are GMT -4. The time now is 08:35 AM.