MAF / Relay question
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MAF / Relay question
Ok, while testing, I found this out.
Normally hooked up
-------------------------
After a minute of the engine being on, the SES light comes on, and returns a code "33" .. which deals with the MAF sensor
Disconnect MAF relay
--------------------------
Car still runs, no codes at all, even after a minute
Reconnect MAF relay, as the car is STILL on
------------------------------------------------------
car hesitates for a minute, and seems to run a tad worse, code 33 pops up, again
Now, I heard about the MAF getting backup power, from somewhere, if the relay fails? Or something like that? It seems like the MAF relay is bad, if this is the case, unplugging it, and it runs BETTER... is this the solution to my **** POOR gas mileage?
Will the computer just not return any codes, if the relay is disconnected? In theory, shouldn't it return codes?
I can shake the MAF relay, and i can hear loose parts. I just want some confirmation on whether or not the car / MAF should run great, with no codes, when the MAF relay is disconnected.
The Relay will probably get replaced, anyways
-- Thanks
John.
Normally hooked up
-------------------------
After a minute of the engine being on, the SES light comes on, and returns a code "33" .. which deals with the MAF sensor
Disconnect MAF relay
--------------------------
Car still runs, no codes at all, even after a minute
Reconnect MAF relay, as the car is STILL on
------------------------------------------------------
car hesitates for a minute, and seems to run a tad worse, code 33 pops up, again
Now, I heard about the MAF getting backup power, from somewhere, if the relay fails? Or something like that? It seems like the MAF relay is bad, if this is the case, unplugging it, and it runs BETTER... is this the solution to my **** POOR gas mileage?
Will the computer just not return any codes, if the relay is disconnected? In theory, shouldn't it return codes?
I can shake the MAF relay, and i can hear loose parts. I just want some confirmation on whether or not the car / MAF should run great, with no codes, when the MAF relay is disconnected.
The Relay will probably get replaced, anyways
-- Thanks
John.
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From: Kempner,TX,
Car: 1996 Vette / 1992 GSX1100F Suzuki
Engine: 1996 Corvette Coupe 388 LT1 (+.060)
Transmission: Auto
Axle/Gears: 3.07
I believe that when you disconnect the relay the ECM switches to Limp Home Mode.
Engine then runs on programmed fuel and spark maps and ignores the 02 and MAF sensor readings.
Jake
Engine then runs on programmed fuel and spark maps and ignores the 02 and MAF sensor readings.
Jake
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Joined: Oct 2002
Posts: 412
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i figured out something else.. i just didn't post yet
Ok... turns out the relay that was broken was my MAF BURN-OFF. and not my MAF power. The relay was labelled "MAF POWER" at the top, thus I figured.... must be the MAF power...
well disconnecting the broken relay, i got no codes
UNTIL i shut the car off, and turned it back on. then I got a BURN-OFF relay code...
So, i replaced the burn-off relay, and everything is fine. I guess the MAF Burn-off was staying in the "ON" position, and was really screwing with the MAF's readings, thus the ECM just gave up and said "I can't deal with this" and put it in limp mode.
Going to replay the Maf POWER relay, anyways, though.
No more codes comin' out of here. hopefully i get better gas mileage... still have an O2 sensor to replace.
Ok... turns out the relay that was broken was my MAF BURN-OFF. and not my MAF power. The relay was labelled "MAF POWER" at the top, thus I figured.... must be the MAF power...
well disconnecting the broken relay, i got no codes
UNTIL i shut the car off, and turned it back on. then I got a BURN-OFF relay code...
So, i replaced the burn-off relay, and everything is fine. I guess the MAF Burn-off was staying in the "ON" position, and was really screwing with the MAF's readings, thus the ECM just gave up and said "I can't deal with this" and put it in limp mode.
Going to replay the Maf POWER relay, anyways, though.
No more codes comin' out of here. hopefully i get better gas mileage... still have an O2 sensor to replace.
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