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Bad MAF?

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Old Dec 8, 2010 | 12:20 AM
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Default Bad MAF?

Drove it on a trip this past weekend. AFR's were good for about the first hour then went south. It was in the 9's to 10's going down the highway, no boost, 5-6 inches of vacuum. Then it went the other way about a half hour later, way lean. This thing is driving me nuts!! Could a bad MAF cause this or something else like the regulator?? I pulled the vacuum line from the regulator and it was dry. This thing has been nothing but problems for me. Any help would be great.
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Old Dec 8, 2010 | 07:50 PM
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could be your MAP sensor....this controlls your fueling to a certain degree
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Old Dec 8, 2010 | 08:10 PM
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what type of tune are you running? 1bar? Does the fueling only do that when cruising but when you get into it it levels out where it should?
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Old Dec 8, 2010 | 08:53 PM
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Yes I believe it is a 1 bar set up. It still has the factory MAP and MAF in it. Black Bear did the tune. Not too familiar with tuning. And when I get in it it goes lean. This thing is driving me nuts. I dont want to throw a bunch of money at either to try and figure it out. Im waiting till after Christmas to do the AutoCal with Justin. Hopefully he can get this figured out. Someone from work told me to buy a bigger MAF, a Hitachi brand and wire it in the same as whats stock. Says the MAF is way to small for the application.
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Old Dec 8, 2010 | 08:56 PM
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Could the injectors be going bad?? They only have 5000 miles on them.
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Old Dec 8, 2010 | 10:32 PM
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A bad MAP sensor will show a lean and rich condition as you mentioned...it will be all over the place.
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Old Dec 8, 2010 | 10:35 PM
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mail order tune?
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Old Dec 8, 2010 | 10:48 PM
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do not buy a bigger MAF....that is bad advice. Contact Justin, he will get you fixed up just fine. Do you have a cable so you can log?
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Old Dec 8, 2010 | 10:49 PM
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Originally Posted by GMCtrk
mail order tune?
Yes from BlackBear Performance. Justin Gadberry.
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Old Dec 8, 2010 | 10:50 PM
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Originally Posted by trever1t
do not buy a bigger MAF....that is bad advice. Contact Justin, he will get you fixed up just fine. Do you have a cable so you can log?
Wasn't going to buy anything until I talk to Justin. No I do not have a cable. What do I need to get? Part numbers etc...
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