Mass Airflow Sensor
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From: Odessa Tx
Mass Airflow Sensor
So I got my 85 finally fired up today and broke the motor in. I set the timing and as I throttle up it is good until I get to where the throttle is open all the way. After about opening half way it began to be sluggish. I unplugged the mass airflow sensor and it ran much better on the top end. I am going to buy a new sesor. Is this probably the main problem?
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maybe
doesnt 85 not have separate burn off relays for the maf? Controlled by ecm ?
Might be maf.
Might be maf.
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From: Tampa Florida
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From: Odessa Tx
It should have that relay... I will try that tomorrow. Is there any way to test the MAFS? I know that I cleaned it out and the wire that is inside is in tact. I did not touch it with anything.
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The 85 had a MAF burn off module.Not the relays like the 86 and later cars had.Its located inside the dash.
Are you getting a code?Engine light?
Also,if you added a larger Throttle body or adjusted the TPS and minim air incorrectly,it can cause a similar problem.I only ask this is because you just started it back up,and I have no idea if you did an adjustment or not.
An incorrected adjusted TPS with the min air speed off can cause a code 33 MAF problem and fall flat on its face.
Are you getting a code?Engine light?
Also,if you added a larger Throttle body or adjusted the TPS and minim air incorrectly,it can cause a similar problem.I only ask this is because you just started it back up,and I have no idea if you did an adjustment or not.
An incorrected adjusted TPS with the min air speed off can cause a code 33 MAF problem and fall flat on its face.
Le Mans Master
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From: Tampa Florida
The 85 had a MAF burn off module.Not the relays like the 86 and later cars had.Its located inside the dash.
Are you getting a code?Engine light?
Also,if you added a larger Throttle body or adjusted the TPS and minim air incorrectly,it can cause a similar problem.I only ask this is because you just started it back up,and I have no idea if you did an adjustment or not.
An incorrected adjusted TPS with the min air speed off can cause a code 33 MAF problem and fall flat on its face.
Are you getting a code?Engine light?
Also,if you added a larger Throttle body or adjusted the TPS and minim air incorrectly,it can cause a similar problem.I only ask this is because you just started it back up,and I have no idea if you did an adjustment or not.
An incorrected adjusted TPS with the min air speed off can cause a code 33 MAF problem and fall flat on its face.
I agree with checking for a correct TPS voltage setting.
Pro
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From: Lubbock for now, headed for Oklahoma
your sooooo right! He may not even be falling in the parameters for a code set. I don't know what they were but the parameters for the older computers where much wider than they are for the newer.
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In my case my '85 had a bad burnoff module and never threw a code. Also, since he cleaned the maf and it didn't help it most likely eliminates the module as a problem. I would do the settings as suggested before buying any parts.
Pro
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From: Lubbock for now, headed for Oklahoma
UH OH! well that may change a few things. With everything that you have already given us and that I am kinda wondering if you have an exhaust restriction.
Catalytic converters and mufflers alike can clog up enough to cause these issues. Do you have a vacuum gauge?
Catalytic converters and mufflers alike can clog up enough to cause these issues. Do you have a vacuum gauge?
Pro
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From: Lubbock for now, headed for Oklahoma
Well that rules that out for sure. Okay well it could still have a bad MAF really to test them you need an oscilloscope. Could be a bad MAP IF your car has one. Or a weak EGR valve spring.
A dirty way to test for EGR is to just unbolt it, put a dime over the hole and bolt it back down on the dime, you can also use a cut piece of an aluminum can.
If you use a dime don't torque it down real tight as the dime is just a close fit but a little big. You can break your EGR.
A dirty way to test for EGR is to just unbolt it, put a dime over the hole and bolt it back down on the dime, you can also use a cut piece of an aluminum can.
If you use a dime don't torque it down real tight as the dime is just a close fit but a little big. You can break your EGR.