85 TPI - MAF fault?
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85 TPI - MAF fault?
Hi all,
I'm getting a 32 and a 34 error code and was told my Mass Air Flow sensor may be bad. I believe there's a way to check this but can't remember. Do any of you know?
thanks,
85_TPI
I'm getting a 32 and a 34 error code and was told my Mass Air Flow sensor may be bad. I believe there's a way to check this but can't remember. Do any of you know?
thanks,
85_TPI
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From: Maryville Tn
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I had a code 32 in with my '85. Code 32 was for the EGR. I replaced the EGR vacuum solenoid for $29.00 and the code went away. Code 34 is for the MAF. Sorry I don't how to test the MAF to see if it's faulty. Let me know what you find out. 
Last edited by H P Bushrod; Jan 3, 2005 at 04:15 PM.
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From: Kempner Texas
Originally Posted by 85_TPI
[COLOR=DarkOliveGreen]Hi all,
I'm getting a 32 and a 34 error code and was told my Mass Air Flow sensor may be bad. I believe there's a way to check this but can't remember. Do any of you know?
thanks,
I'm getting a 32 and a 34 error code and was told my Mass Air Flow sensor may be bad. I believe there's a way to check this but can't remember. Do any of you know?
thanks,
How's the engine running?
I'd first check to be sure that the MAF connector is firmly plugged in.
I'd then disconnect the battery for about 30 seconds to clear the stored codes and restart the engine to see if the codes return. If the MAF code returns, I'd remove the MAF and check the two thin wires to see if either is broken.
If the wires check okay, re-install the MAF, start the engine and tap the bottom on the MAF with the handle of a screwdriver. If the engine stumbles, the MAF is bad.
There are a series of voltage tests that can be run on the MAF connector wires. I believe I saved a doc file showing which ones should read what. The file's for an 86 but I believe they're the same as for the 85.
Keep us posted.
Jake
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Originally Posted by 85_TPI
Hi all,
I'm getting a 32 and a 34 error code and was told my Mass Air Flow sensor may be bad. I believe there's a way to check this but can't remember. Do any of you know?
thanks,
85_TPI
I'm getting a 32 and a 34 error code and was told my Mass Air Flow sensor may be bad. I believe there's a way to check this but can't remember. Do any of you know?
thanks,
85_TPI
One, disconnect it, if car runs better suspect the MAF
Two, with MAF connected, and car running, tap it fairly firmly but not hard, with a screwdeiver handle. if car stumbles, suspect the MAF
If none of the above, replace the MAF relays
I use a scan tool, good investment, to give me voltage readings, etc. not just the codes the computer has. This has saved me a lot of money vs. trying lots of new parts in hopes something works
Jack
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MAF Fault
I've performed the meter tests on the harness going to the MAF connector and they check good while turning the key on & off.
Had the car running and disconnected the MAF with no apparent difference. With MAF disconnected, the car definitely stumbles but can accelerate if I try, very slowly.
Thanks for all of your responses.
This forum is a lot better than I had expected...
85_TIP
Byron, Ga.
Had the car running and disconnected the MAF with no apparent difference. With MAF disconnected, the car definitely stumbles but can accelerate if I try, very slowly.
Thanks for all of your responses.
This forum is a lot better than I had expected...
85_TIP
Byron, Ga.
Burning Brakes
Joined: Feb 2003
Posts: 1,246
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From: SouthBend IN
Man i had this exact problem with my 85 when i first got it. Turned out to be the plug was not making contact where it plugs into the MAF. unplug it and use a small screw driver to tighten uo the metal tabs inside there, then plug it back in. This fixed mine after 3 days of checking everything. A fellow forum member named Ralph from GA. helped me with mine. You can unhook the MAF, set it up where you can see it with the plug plugged in and then jumper 2 parts on the ALDL and the wire inside should glow when you turn the key to the power position...i just can't remember which 2 ports on the ALDL.
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One of the tests that I wasn't sure how to run(because of my inexperience) is getting the "burn-off" wire to glow.
The test, as described from the alldatadiy.com website, stated for me to "ground" the E terminal on the ALDL and then turn the key on & off.
The thing I wasn't sure about was exactly how to "ground" it. Do I just jumper it to another terminal or go to a ground point outside of the ALDL or what?
thanks for any input,
85_TPI
Byron, Ga.
The test, as described from the alldatadiy.com website, stated for me to "ground" the E terminal on the ALDL and then turn the key on & off.
The thing I wasn't sure about was exactly how to "ground" it. Do I just jumper it to another terminal or go to a ground point outside of the ALDL or what?
thanks for any input,
85_TPI
Byron, Ga.
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No, the test I performed was to connect at terminal E on the harness-side and make sure the voltage was over 10(which it was) and that it stayed that way for 4-8 seconds after the key was turned off(successful here too). 
The next test was to check the fourth terminal(D) and ensure that the voltage was less than 1(it was).
I'm assuming that the ALDL has a 'ground' terminal and that I need to just jumper from that to the E terminal and turn the key on for 10 seconds and then off again, and look to see if the burn-off wire, glows.
Is this correct?
thanks for the input,
85_TPI
Byron, Ga.
The next test was to check the fourth terminal(D) and ensure that the voltage was less than 1(it was).
I'm assuming that the ALDL has a 'ground' terminal and that I need to just jumper from that to the E terminal and turn the key on for 10 seconds and then off again, and look to see if the burn-off wire, glows.
Is this correct?
thanks for the input,
85_TPI
Byron, Ga.
Burning Brakes
Joined: Feb 2003
Posts: 1,246
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From: SouthBend IN
the test sounds right, but i don't have the letters on the ALDL memorized.
I feel your pain, i took the whole dash out, checked some little box behind the dash and finally found the connector to not be making good enough contact. This is why my car is now carburated. 3 wires to run, starter,dist,fuelpump.
I feel your pain, i took the whole dash out, checked some little box behind the dash and finally found the connector to not be making good enough contact. This is why my car is now carburated. 3 wires to run, starter,dist,fuelpump.
Burning Brakes
Joined: Feb 2003
Posts: 1,246
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From: SouthBend IN
well it's not for everone. But mine is just as driveable as the TPI was because my combo is mild.
12.63@109 motor
11.38@118 100 shot
10.98@124 150 shot
250 shot coming this spring, trying for 10.50 @130.
car still has 15" of vac and elec choke carb
Mike
12.63@109 motor
11.38@118 100 shot
10.98@124 150 shot
250 shot coming this spring, trying for 10.50 @130.
car still has 15" of vac and elec choke carb
Mike
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Originally Posted by JAKE
How's the engine running?
I'd first check to be sure that the MAF connector is firmly plugged in.
I'd then disconnect the battery for about 30 seconds to clear the stored codes and restart the engine to see if the codes return. If the MAF code returns, I'd remove the MAF and check the two thin wires to see if either is broken.
If the wires check okay, re-install the MAF, start the engine and tap the bottom on the MAF with the handle of a screwdriver. If the engine stumbles, the MAF is bad.
There are a series of voltage tests that can be run on the MAF connector wires. I believe I saved a doc file showing which ones should read what. The file's for an 86 but I believe they're the same as for the 85.
Keep us posted.
Jake
I'd first check to be sure that the MAF connector is firmly plugged in.
I'd then disconnect the battery for about 30 seconds to clear the stored codes and restart the engine to see if the codes return. If the MAF code returns, I'd remove the MAF and check the two thin wires to see if either is broken.
If the wires check okay, re-install the MAF, start the engine and tap the bottom on the MAF with the handle of a screwdriver. If the engine stumbles, the MAF is bad.
There are a series of voltage tests that can be run on the MAF connector wires. I believe I saved a doc file showing which ones should read what. The file's for an 86 but I believe they're the same as for the 85.
Keep us posted.
Jake
I would like to see those instructions, if you can locate them. Do you mind?
85_TIP
Byron, Ga
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Sorry to keep bugging you nice people but I may be getting confused, not sure.
I completed the "burn-off" test and I was able to see the tiny wire inside the MAF "glow" for about one second and then went out.
If I'm not mistaken, this is correct functioning of the burn-off process and the voltage coming from the harness checks good too.
I think it's still possible for the MAF to perform a burn-off but the Air Flow sensing part of the MAF could still be bad.
Am I on the right track here?
thanks,
85_TPI
Byron, Ga
I completed the "burn-off" test and I was able to see the tiny wire inside the MAF "glow" for about one second and then went out.
If I'm not mistaken, this is correct functioning of the burn-off process and the voltage coming from the harness checks good too.
I think it's still possible for the MAF to perform a burn-off but the Air Flow sensing part of the MAF could still be bad.
Am I on the right track here?
thanks,
85_TPI
Byron, Ga
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Okay, this is the status on my '85 L98...
It doesn't seem to matter if the MAF is on or off the car, it backfires back through the intake when I try to accelerate quickly but once it warms up a little, I can rev it up a little better but I still get backfiring when I goose it some.
Also, there some pinging/popping noise coming into the EGR valve and I was told that it could be a sticking EGR but I now have the EGR off the intake and can suck through the vacuum tube and I'm getting it to respond.
I'd like to take it for a spin but it's really popping too much to even get it off the ground, pretty much.
I plan to replace the MAF unless someone advises otherwise.
I may just need to replace the EGR too but I don't understand why the engine is making the noise through there.
thanks Moocho for any input,
85_TPI
Byron, Ga
It doesn't seem to matter if the MAF is on or off the car, it backfires back through the intake when I try to accelerate quickly but once it warms up a little, I can rev it up a little better but I still get backfiring when I goose it some.
Also, there some pinging/popping noise coming into the EGR valve and I was told that it could be a sticking EGR but I now have the EGR off the intake and can suck through the vacuum tube and I'm getting it to respond.
I'd like to take it for a spin but it's really popping too much to even get it off the ground, pretty much.
I plan to replace the MAF unless someone advises otherwise.
I may just need to replace the EGR too but I don't understand why the engine is making the noise through there.
thanks Moocho for any input,
85_TPI
Byron, Ga
