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Old 02-20-2008, 05:04 PM
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icsmike
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Default MAF testing

Im lookingfor a way to tell if your MAF is not working like it should? Maybe I could ship it to someone for testing?
Old 02-20-2008, 05:41 PM
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bgibby
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www.injectionlabs.com
Old 02-20-2008, 05:44 PM
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icsmike
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Whats it worth to someone for me to ship it to you and you test it in your car?
Old 02-20-2008, 05:58 PM
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928autobahndreamer
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I'm not sure if MAFs from 86.5 are compatible with an 87 (maybe somebody can chime in with the answer), but if you want to drop by we could try swapping with my car and see if there is a difference. Shoot me a PM if you are interested. If the car is not drivable I could try and swing by. I am not sure what things look like this weekend, but I could probably break free for a couple of hours. That is if there is not snow on the roads.
Old 02-20-2008, 06:11 PM
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ROG100
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I can test it for you and also offer a rebuild if required.
MAF's from 85 to 95 are the same.
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Old 02-20-2008, 06:27 PM
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Jim bailey - 928 International
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The 85-86 cars however the "adjustment screw" on the mass air actually talks to the brain...87> that ciruit is not connected to the brain. Same unit slightly different applications.
Old 02-20-2008, 07:25 PM
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Cool! two great offers.
Old 02-20-2008, 07:48 PM
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blitz928
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One trick to test the MAF sensor was to disconect it at idle and if the car idled better without it, it may be bad.
Old 02-20-2008, 09:57 PM
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Even better idea - I send you a rebuilt MAF and if that improves your car you buy it and I get yours as a core all for $350 plus $10 shipping. You don't need it and you are out the shipping including back to me.
Roger
Old 02-21-2008, 03:01 AM
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icsmike
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Roger, that is by far the most amazing, trusting offer I have ever heard on this board. I'm a man of my word and self employed. I also do these types of services for my customers, and I think its a dying thing.
Sounds like a great offer to me. Thanks!!!!
Old 02-21-2008, 12:43 PM
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I made a MAF voltage monitor so that it becomes easy to see what the MAF is doing and how the ecu / lambda sensor respond. That works great. Here's a link to my page showing the device I made and a little flash movie.
http://jenniskens.livedsl.nl/Technic...AF%20meter.htm

The blue curve is the MAF voltage in 0.5v per LED. The other is the lambda. Not too hard to make yourself. Nope, I'm not offering anything for sale.

** I was amazed about the MAF voltage at idle. Already close to 3 volts. Is that a normal voltage?

You see the response of a small gas blip, and the MAF responding brisk, the lamdba following moments later with a change in output (basically the ecu responding to fuel demand). Nice to see the system at work like this.

regards,
Theo
Old 02-21-2008, 02:13 PM
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John Speake
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2.7v at idle is more typical for 5 littre engines.
Old 02-21-2008, 03:18 PM
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Thanks John, that sounds just right if I compare to what I see.
I have about 3v at cold, idle, and it drops to 2.5v at idle when warm.
The LED meter is a bit rough and intended as an indicator, not to measure precisely. I will hook up my Fluke to have good measurement. But expect it to be close to 2.7 volts.
regards,
Theo



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