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Help with MAF/computer issues

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Old 12-05-2007, 06:06 AM
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Default Help with MAF/computer issues

I have a really weird problem. I have a SES light, and got the code read, It was P0102 Mass Air Flow (MAF) Circuit Low Input. The car died on me once or twice while I was driving, but started right back up. Lately, I've had to wait 30-45 minutes on the side of the road after it dies on me. It will crank, but won't turn over. I've tried resetting the PCM (disconnecting battery, removing fuses) and cleaning the MAF out with carb cleaner with no effect. The issue seems to be getting worse. Could this be caused by a bad MAF or PCM? The car was just removed from storage for a year, (car was started and driven around the block once a quarter, tank was empty when car was delivered to me) and didn't have any SES light when put into storage. Any suggestions? The car is a 2000 TA, LS6 intake, lid, LT headers, ORY, exhaust, Z06 cam, no tune.

EDIT: BTW, the fuses are all good.

Last edited by Snootch; 12-05-2007 at 07:00 AM.
Old 12-05-2007, 10:16 AM
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I don't think carb cleaner helped it any. You may need to replace it but give it a really good cleaning first. do a search and you'll find how to clean it. the MAF is veeeeery sensitive. Pretty much how it works is the thin wire in the middle is heated to a really high temp, and as air passes over it the maf reads how much voltage it takes to keep it at that temp. I don't know this for a fact but I read somewhere that when you turn the car off it heats that wire to an ungodly amount to help self clean it so you get more accurate readings. but if there was more on it then normal contaminants in the air it probably got cooked or coated with something and is reading completely off
Old 12-05-2007, 11:51 AM
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Are you sure the ENG SEN fuse isn't blown? Buddy of mine threw P0102 and the fuse was open because one of the 02 wiring harnesses was melted against his LT. If it's good, time to do a full diagnosis - www.gearchatter.com/viewtopic9069.php
Old 12-05-2007, 07:50 PM
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unplug it and the car should run just fine untill you get another one if it does thats your problem
Old 12-08-2007, 10:43 PM
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unplugging it wont fix the problem and spraying any cleaner on the maf will ruin it very fast there is no way to clean them, and it dont sound like a pcm prob. i would just go ahead and change the maf if it were me b/c either way it hs been damaged by the cleaner that was sprayed into it. hope tis may help its not much but just from exp. it worth a shot man
Old 12-09-2007, 02:03 AM
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Originally Posted by 2001NBMZ28
Are you sure the ENG SEN fuse isn't blown? Buddy of mine threw P0102 and the fuse was open because one of the 02 wiring harnesses was melted against his LT. If it's good, time to do a full diagnosis - www.gearchatter.com/viewtopic9069.php
Same thing happened here and that was the code i got.
Old 12-10-2007, 03:11 PM
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Originally Posted by AJ93LT1
unplugging it wont fix the problem and spraying any cleaner on the maf will ruin it very fast there is no way to clean them, and it dont sound like a pcm prob. i would just go ahead and change the maf if it were me b/c either way it hs been damaged by the cleaner that was sprayed into it. hope tis may help its not much but just from exp. it worth a shot man
I didnt say unplugging it would fix it. it will allow him to diagnose the problem before buying a new maf though. if you unplug the maf and drive the car and the problem isnt there then the maf is your priblem if you have the same symptoms as before then he'd need to look else where. Adnd the is a way to clean a MAF its called MAF cleaner and they sell it at almost all parts stores
Old 12-10-2007, 10:22 PM
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Not sure what rock you came out from under but carb cleaner will not damage the MAF. We have cleaned many mafs through the years at shop that have been oiled by careless users of cleanable reusable airfilters.
Old 12-26-2007, 12:45 PM
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Okay, I replaced the MAF and TB, and I still have the issue. It now runs for 10-15 minutes then dies and will not restart. Can anyone shed some light on this? This really sucks because my other car has been getting worse (bad wheel/axle bearing) and if it breaks, I am walking. BTW, the ENG SEN fuse is good.

Last edited by Snootch; 12-26-2007 at 01:00 PM.
Old 12-27-2007, 01:47 AM
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Bump.

Seriously need some help here guys. Anyone?
Old 01-03-2008, 05:33 AM
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I started it today, and is ran for 4 minutes before dying. It actually started again immediately, and ran for 5 minutes before dying again. It would not start again, only crank, and crank. Does anyone have any idea what this problem is? I've replaced the MAF once already, and all the fuses are good.
I don't think there is a GM dealer anywhere in this part of Italy, and If I have to have it towed into town to have it worked on, it'll cost me upwards of $500. (Ihad it towed 1.3 miles from home when this problem started initially, and it cost me 100 euros ($160) to have it towed)

So any help would be seriously appreciated. Thanks!
Old 01-04-2008, 09:36 PM
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check the harrness for the maf.
Old 01-05-2008, 11:43 AM
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Originally Posted by fuseone
check the harrness for the maf.
I ran the car today with the MAF un-plugged and it still died in 4-5 minutes. I guess this leads me to believe its a computer or wiring problem. How would I check the harness, strip the covering off it as far as possible, then look for shorts?
Old 01-05-2008, 12:50 PM
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could do that but i would think to check for exessive voltage drop
Old 01-05-2008, 01:14 PM
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i would def check those 02 wiring harnesses under there u never kno that might be the problem i had the same trhin but my fuse was blown so i dunno but do check it, i was goin insane when this was doin it to me, so i dunno, i would def double check it all under there...
Old 01-05-2008, 01:30 PM
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Originally Posted by leoni62486
i would def check those 02 wiring harnesses under there u never kno that might be the problem i had the same trhin but my fuse was blown so i dunno but do check it, i was goin insane when this was doin it to me, so i dunno, i would def double check it all under there...
would the o2 harness cause that code?
Old 01-05-2008, 05:55 PM
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Originally Posted by fuseone
could do that but i would think to check for exessive voltage drop
What should the voltage be at the MAF plug?

oh, and I have headers installed (no O2 sensors) should I look at the wiring there for obvious shorts in the wiring?
Old 01-05-2008, 09:13 PM
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wait so no o2 sensor or just no rear o2's? and im pretty sure it should be 5volts. but you would have to check volt drop across the ground side also not just total voltage
Old 01-06-2008, 05:37 AM
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Originally Posted by fuseone
wait so no o2 sensor or just no rear o2's? and im pretty sure it should be 5volts. but you would have to check volt drop across the ground side also not just total voltage
The headers I have do have O2 bungs on them. I was under the impression those were the only o2 sensors. I had a shop do the install, I assume they used O2 sims, or programmed them out.

My MAF voltages (motor running > 1 minute) are: Black-Pink: 14vdc Black-Yellow: 4.5-5.0vdc

Last edited by Snootch; 02-05-2008 at 01:31 PM.
Old 01-10-2008, 10:08 AM
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Quick question, Could it possibly be an O2 sim going bad? If that happened, wouldnt the computer throw a different code? I'm thinking maybe over the year the car was in storage maybe the o2 sims went "bad" or something. Also, since the header install, do they have to mess with the rear o2 sensors? are they located on the y-pipe? and if they are, then possibly could they be going bad, even though i'm seeing 12vdc at the MAF?

EDIT: I just got out from under the car, and there ARE o2 sensors on the headers. It looks like the guys that installed my headers cut the o2 wires, and shortened them. The splice looks good- barrel-crimp connectors wrapped with shitloads of electrical tape. Should I just get some new o2 sensors from the dealer (or GM parts direct) and replace them?

Last edited by Snootch; 01-10-2008 at 12:15 PM.



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