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MAP vs MAF


3pt1lumina

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MAP is used on all 3.1s (except some latter 3100s I think maybe got MAF?)

 

The 1988 2.8 had both MAF and MAP, then in 89 the MAF was dropped...

 

OBD II+ 3100's got the MAF sensor.

 

Okay that explains why I cannot locate a MAF for the car :oops: :lol: (Yes and I admit to it too.)

 

What's the symptoms of a MAP going bad? Easy to replace I am assuming?

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Can someone please explain the difference? Which of these are used on the 3.1 Gen II motors? And what are the symptoms of each going bad?

 

Thanks 8)

 

A MAP uses the pressure in your intake manifold to determine how much fuel (along with other sensors) to inject. A MAF measure how much air is flowing in to determine fuel. The older MAFs do not do a very good job, thus the upgrade to MAP.

 

If the MAP is going bad, the car wont have any power, it'll idle rough and stumble if you get on the gas.

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MAP stands for manifold absolute pressure, MAF stands for mass air flow. 3100 W's use the MAP sensor and air intake temp sensor to help compute the air fuel ratio. The air intake temp sensor tells the computer how dense the incoming air intake charge is and the MAP sensor reads engine vaccuum, IE engine load. This is called the speed density method. Late model W's use a MAF sensor.

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Also, I forgot to mention, 94-94 Olds Achieva's and Cutlass Ciera's used a MAF on the 3100 engine, but they were only actually rated at 155 hp instad of 160 like in the MAP equipped W cars.

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there are three wires that go to the MAP sensor. Piggy back into the harness by probing into the backside of it with a volt testor. One wire is a 5volt, the other is a reference varying in voltage and the last is a ground. unplug and turn ignition to on and find your 5 volt wire. Then backprobe the other two with the car running. As you change the pressure in the manifold by opening and closing the throttle, the reference voltage should change.

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Say I have a 1996 3100 in my GP, using MAF (I think due to the large thing on the intake hose, almost positive that's MAF). Is there any other MAF's I can rip off another car and use that gets better flow and a better reading? I mean if you look at the one in there now it uses this tight metal grate facing the airbox, which I know is just KILLING flow... but i've seen MAF's on other cars that were just a few metal wires.

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Say I have a 1996 3100 in my GP, using MAF (I think due to the large thing on the intake hose, almost positive that's MAF). Is there any other MAF's I can rip off another car and use that gets better flow and a better reading? I mean if you look at the one in there now it uses this tight metal grate facing the airbox, which I know is just KILLING flow... but i've seen MAF's on other cars that were just a few metal wires.

 

Does your car you have the Hitachi MAF? If so,it flows more than youll ever use.The screen also helps diffuse the airflow inside the sensor.I have one on my 95 Olds van 3800 and its a far better design than the former bosch junkers on other GM cars.You can actually clean this sensor inside of the carbon where the older cars,had a heated wire,you risked breaking it and failure was a when,not will it break?

 

Ive experimented with Bosch MAF for 5.7 350 TPI corvettes and removing the screens on modified engines did nothing to gain any noticeable power.Those powerplants are much larger and suck in alot more air though but doing that mod didnt justify anything,even with the internal heat sinks cut out.

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