Maf
04-15-2003, 06:43 PM
#2
Guest
Posts: n/a
First off, post your reply under you original post, things just work better that way.
Anywhoo, the MAF is attached to the airbox. It's the first place air enters after it goes through the air filter and the airbox. I'm sure there's a way to directly test it, but I wouldn't bother doing it that way. All you have to do is take out the ECU from underneath the passenger seat and checking the codes on it, it'll tell you if you have a bad MAF. Also, an even easier way to test it is to press down on the gas. If the car won't rev past 2000 rpm, then it's definitely bad. The MAF tells the ECU how much fuel to put in the engine according to the volume of air coming in. When the MAF goes bad, the ECU doesn't know, so it has a preprogrammed amount that will allow you to "limp home" so you aren't stranded. That's why it will drive up to 2000 rpm.
If you determine that your MAF is bad, you may want to see if the air injection valve (AIV) is leaking water into your airbox. You may see a puddle of water at the bottom of the airbox. The AIV connects to the airbox via a hose, near where the MAF connects to. When the AIV's go bad, they tend to leak into there and end up destroying the MAF sensor. My AIV was destroyed during emmissions testing and I had to find out the hard way.
MAF's aren't cheap either, they go for about $400 new, though you can pick them up at a junkyard for around $100. The procedures to fix and diagnose this stuff are in the Chilton's, Haynes, and Factory Service Manual (FSM). You may want to pick one of those up. There's also a wealth of info here and at the club (listed in my sig), so look around, you can find all the info that you need.
-C-
Anywhoo, the MAF is attached to the airbox. It's the first place air enters after it goes through the air filter and the airbox. I'm sure there's a way to directly test it, but I wouldn't bother doing it that way. All you have to do is take out the ECU from underneath the passenger seat and checking the codes on it, it'll tell you if you have a bad MAF. Also, an even easier way to test it is to press down on the gas. If the car won't rev past 2000 rpm, then it's definitely bad. The MAF tells the ECU how much fuel to put in the engine according to the volume of air coming in. When the MAF goes bad, the ECU doesn't know, so it has a preprogrammed amount that will allow you to "limp home" so you aren't stranded. That's why it will drive up to 2000 rpm.
If you determine that your MAF is bad, you may want to see if the air injection valve (AIV) is leaking water into your airbox. You may see a puddle of water at the bottom of the airbox. The AIV connects to the airbox via a hose, near where the MAF connects to. When the AIV's go bad, they tend to leak into there and end up destroying the MAF sensor. My AIV was destroyed during emmissions testing and I had to find out the hard way.
MAF's aren't cheap either, they go for about $400 new, though you can pick them up at a junkyard for around $100. The procedures to fix and diagnose this stuff are in the Chilton's, Haynes, and Factory Service Manual (FSM). You may want to pick one of those up. There's also a wealth of info here and at the club (listed in my sig), so look around, you can find all the info that you need.
-C-
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