Question about Burn off box
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Joined: Mar 2004
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From: wichita kansas
Question about Burn off box
I have a 1985 and i was wondering what a burn off box is? could that be the reason that my car will not idle some of the time i dont think my MAF sensor is out and theres not error codes please help!
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
Re: Question about Burn off box (BrettWithVette)
It's actually a relay, a burn-off relay.
When you shut down the engine, the relay sends 12 volts to the MAF through the MAF power relay to burn-off any contaminates on the MAF sensor wires.
A bad burn-off relay will set code 36.
Jake
When you shut down the engine, the relay sends 12 volts to the MAF through the MAF power relay to burn-off any contaminates on the MAF sensor wires.
A bad burn-off relay will set code 36.
Jake
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Re: Question about Burn off box (BrettWithVette)
Its a module, that in 85 only is sitting behind the passenger side dash.
You only have the one, and its kinda expensive because its unique to your year.
You dont have a burnoff/power relay behind the battery like 86-89 does.
Its possible the idle is related, but only after checking plugs/wires/cap/rotor and then the IAC and TPS setting.
EDIT, and look for vacuum leaks
[Modified by vader86, 8:37 PM 4/24/2004]
You only have the one, and its kinda expensive because its unique to your year.
You dont have a burnoff/power relay behind the battery like 86-89 does.
Its possible the idle is related, but only after checking plugs/wires/cap/rotor and then the IAC and TPS setting.
EDIT, and look for vacuum leaks
[Modified by vader86, 8:37 PM 4/24/2004]
Racer
Joined: Dec 2003
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Re: Question about Burn off box (vader86)
:iagree: correct, if i am not mistaken it is the same part used in early F bodies in 85 with TPI. After 85 they went with the 2 relays. At shut down the MAF wire is cleaned by the current flow thru the sensor wire, you can watch it glow red at shut down, or simulate a shut down, ign. key on then to off. ....
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
Re: Question about Burn off box (BrettWithVette)
Wouldn't it be nice if the Forum had a way to distinguish all those years and engines that have unique characteristics that aren't present in ALL C4s.
Like the Opti-Spark, dry intake, reverse cooling, and, yes, burn-off box behind the dash (and not in the engine compartment), MAF, MAP, etc.
This stuff is so confusin' makes my head hurt. Think I'll go have a "shot" of something.
Jake
Like the Opti-Spark, dry intake, reverse cooling, and, yes, burn-off box behind the dash (and not in the engine compartment), MAF, MAP, etc.
This stuff is so confusin' makes my head hurt. Think I'll go have a "shot" of something.
Jake
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From: wichita kansas
Re: Question about Burn off box (JAKE)
ok well i can get a burn off box off of ebay for 39 dollars but i kinda want to know if u guys think its worth it cause i dont want to waist the money if its not gonna solve anything cause its not giving any codes it just dies some times at idle and sometimes it dosent its weird when i run it for a while it will correct it self and not act up i have checked the maf senor the wire lead and even took out the chip in the comp. im out of ideas please help me im on my knees!!! :beatdeadhorse:
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
Re: Question about Burn off box (BrettWithVette)
Well, I don't know if a bad one would set a code or not, since others say it's a unique part.
I don't recommend throwing parts at a problem unless I know the part to be replaced is bad.
I'd first clean the butterflies on the throttle body and the IAC pintel and inside the housing it screws in to. I'd then check for the proper operation of the 02 sensor, MAF and that the ignition timing is correct.
Check first, but parts later.
Jake
I don't recommend throwing parts at a problem unless I know the part to be replaced is bad.
I'd first clean the butterflies on the throttle body and the IAC pintel and inside the housing it screws in to. I'd then check for the proper operation of the 02 sensor, MAF and that the ignition timing is correct.
Check first, but parts later.
Jake
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Drifting
Joined: May 2002
Posts: 1,509
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From: Hazel Park MI
Re: Question about Burn off box (JAKE)
:iagree: Better check some other things first. Burn off module up in the dash, passenger side behind the bread box, burn off relay behind the battery. :seeya
Racer
Joined: Dec 2003
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Re: Question about Burn off box (BrettWithVette)
check yours first, remove the MAF sensor air hose, leave the wires etc intact, you want to have it so you can look into the MAF sensor, ignition switch ON, ground the ALDL term E, shut the ign off and quickly look at the MAF sensor and see it the wire glows, if so its a good Module. A helper to view the sensor can be helpful as the whloe proecess will be complete in about 10 seconds.
