MAF on my '87 2,8L V6 gives constantly 2,6V voltage (between B & C wires). Does it means, that my MAF is dead? I have tried one MAF from junkyard, it gives the same voltage.

What is resistance of MAT (IAT) sensor on your cars? To example @ 20 degrees Celcius? On my Camaro resitance of MAT sensor was ~2,5k ohm. Is that OK, or too low?

 

I'm not sure if you can tell if a MAF's bad by checking voltage... I believe the MAF puts out AC voltage and varies the frequency. I'll look in my GM book tonight to see if it mentions such a method. But anyway, here's my MAT resistance chart.. you'll have to scroll down this page to see it. For some reason, whenever I post a table, it shows up 5 or 6 lines below where it should.

<table BORDER=3 CELLSPACING=3 CELLPADDING=3 >
<tr><td>Temp F</td><td>Temp C</td><td>Ohms</td></tr>
<tr><td>210</td><td>100</td><td>185</td></tr>
<tr><td>160</td><td>70</td><td>450</td></tr>
<tr><td>100</td><td>38</td><td>1,600</td></tr>
<tr><td>70</td><td>20</td><td>3,400</td></tr>
<tr><td>40</td><td>4</td><td>7,500</td></tr>
<tr><td>20</td><td>-7</td><td>13,500</td></tr>
<tr><td>0</td><td>-18</td><td>25,000</td></tr>
<tr><td>-40</td><td>-40</td><td>100,700</td></tr>
</table>


------------------
-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

Thanks alot, TomP! I didn't know, that MAF varies freguency... My Haynes says, that it must change voltage between 0,5-4,7V.

But what about O2 sensor, if it shows ~0,25V below 2500-3000rpm and about 0,7-0,8 over 2500-3000rpm. If rpm drops below ~2500, it gives again 0,25-0,3V. I have measured that with warm engine, with voltmeter, not at driving. Is my O2 OK?