MAF keeps dying
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From: sw Ohio
MAF keeps dying
I had the original MAF fail earlier this year. Got a good used one in August and it just died. Is there something that can cause them to fail like a bad relay or something?
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From: sw Ohio
Yes but the replacement was a BOSCH and it failed in 2 months. I've heard NAPA sells a good rebuilt unit, best place to buy?
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From: The Top of Utah
Originally Posted by Demonic85
Yes but the replacement was a BOSCH and it failed in 2 months. I've heard NAPA sells a good rebuilt unit, best place to buy?
Originally Posted by Demonic85
Got a good used one in August and it just died.
RACE ON!!!
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From: sw Ohio
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From: The Top of Utah
So following the manual part way leads you to the conclusion the MAF is bad? From your post, all the problems didn't disappear. It sounds like similar symptoms both before and after. That makes it sound as though you have more trouble shooting to do. A used MAF cured the problem briefly, but what your trouble shooting DIDN'T do was find what killed the first MAF, and the second one, too. Imagine that! With an unlimited budget, you can keep throwing money at it, forever. Otherwise, a FIX may end up lasting longer than a band aid.
RACE ON!!!
RACE ON!!!
Thread Starter
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From: sw Ohio
So following the manual part way leads you to the conclusion the MAF is bad? From your post, all the problems didn't disappear. It sounds like similar symptoms both before and after. That makes it sound as though you have more trouble shooting to do. A used MAF cured the problem briefly, but what your trouble shooting DIDN'T do was find what killed the first MAF, and the second one, too. Imagine that! With an unlimited budget, you can keep throwing money at it, forever. Otherwise, a FIX may end up lasting longer than a band aid.
RACE ON!!!
RACE ON!!!
Race Director
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From: The Top of Utah
Any suggestions on what might be killing them??? I looked through the FSM and didnt see anything about it except for the unplugging it or substituting for a known good one. I havent thrown any more money at it and dont plan to until I find whats causing this. MAFs aint cheap!
Originally Posted by Demonic85
I've heard NAPA sells a good rebuilt unit, best place to buy?
RACE ON!!!
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From: sw Ohio
However, I did find that '85 is the only year to have a Burnoff Module instead of the relay used on later MAF cars. I unclipped the MAF from the air filter, turned the car on, shut it down, and the MAF did not glow like its supposed to when burning off at shutdown. You can hear a whirring and then click right after shutdown but I think it might be the fuel pump or the fuel pump relay. I took the MAF off and used electrical contact cleaner on it, let it dry, then put it back in. Same results as before.
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From: The Top of Utah
Originally Posted by Demonic85
I know it doesnt seem right, but thats all it said in the diagnostics and fuel delivery sections. Unfortunately I dont have the electrical part of the FSM, so there could be more in there
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From: sw Ohio
Not a single one. When I unplug the MAF and run the car it gives me a code then. I'm starting to lean towards the MAF burnoff module because its never been replaced and it doesnt seem to be burning off. I heard you had to run the car for at least 5 minutes to get the burnoff to work though, so then I wouldnt know if it worked or not. Heres the problem I cant get past regardless.... it dies whenever I give it any amount of gas. Starting it with the pedal on the floor doesnt help.
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From: Cincinnati, Oh USA
I don't know about the 85, I have an 87 and you can unplug the MAF and the engine will run on a lookup table in the computer and it has a relay to power the MAF and a relay to operate the burn off. An error code will set if either relay fails. I will ask my vette mechanic about your problem and see what he says.
Pro
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From: Plano TX
That IS the FACTORY manual, right? How about if you follow the chart for whatever the MAF trouble code is? I don't think the electrical manual would help you in this case. From general reading, I do recall that new relays are often the cure for MAF problems. One more reason I say trouble shoot, and don't throw money at problems. The cure may not be in the obvious place.
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I don't have my 85 FSM on me here, but I'm pretty positive in the engine emissions section (6C or something like that) it has a troubleshooting chart for the MAF. You may or may not be throwing the code, but I'd go ahead and troubleshoot based on that first if that's what you suspect is the issue. I found it very helpful in my no start situation post rebuild recently. I bet with some reading in there you'll figure it out. You may also want to check the symptoms section. That'll help lead you in the right path.
I'll try to remember and grab mine tomorrow and will let you know what I see.
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From: sw Ohio
No K&N here, just good old cotton. I'm still running down the flow chart I found in section 6C of the FSM (doh! I missed it before). If it does turn out to be a bad MAF burnoff module, can I just unplug it? The later MAF's found on the LT1's dont have a burnoff feature at all.
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From: altered state
St. Jude Donor '05
In not sure about the 85s but on the later MAF C4s its said to always replce the burnoff relay when replacing the MAF to prvent a failur on the new piece. Again I see yours uses a module (?) so I dont know whow accurate that is. Check it out.
Does the pigtail (plug) fit good and tight?
Edit: Oops ,didnt see CFI's last post
Does the pigtail (plug) fit good and tight?
Edit: Oops ,didnt see CFI's last post
Last edited by cv67; Nov 24, 2007 at 11:10 AM.
Pro
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From: Plano TX
In not sure about the 85s but on the later MAF C4s its said to always replce the burnoff relay when replacing the MAF to prvent a failur on the new piece. Again I see yours uses a module (?) so I dont know whow accurate that is. Check it out.
Does the pigtail (plug) fit good and tight?
Does the pigtail (plug) fit good and tight?
It's recommended to change both the burn off and power relay if I remember correctly.
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From: sw Ohio
In not sure about the 85s but on the later MAF C4s its said to always replce the burnoff relay when replacing the MAF to prvent a failur on the new piece. Again I see yours uses a module (?) so I dont know whow accurate that is. Check it out.
Does the pigtail (plug) fit good and tight?
Does the pigtail (plug) fit good and tight?
I went through the FSM and it told me to go to the intermittents section, which again states that if disconnection of the MAF cures the problem, then replace the MAF. All because I didnt get any codes. I'm going to go back through the book to see if it could be a faulty computer or something.
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From: altered state
St. Jude Donor '05
If it helps for reference I had a faulty MAF that would imtermittently act up for a year and a half...No engine light ever. Would go dead lean out of the blue and then stop although it seemed to run fine, only way I found out was by reading a dyno sheet that showed A/F mixture.Sometimes the light on the dash doesnt tell all...Wound up eating a head gasket over that one.