What causes this?

Subject: Re: What causes this? Wed Oct 31, 2012 12:50 am

I suspect your MAF is toasted, needs to be replaced. They don't last forever, they are kind of like incandescent light bulbs -- eventually the filament gives out. At your car's age you might be due.

Subject: Re: What causes this? Wed Oct 31, 2012 7:40 am

Before your trims were near normal w/ MAFF plugged in. The OEM sensor is top quality and can last the life of the car, so I would be very sure before spending the money to replace with a lessor one.

_________________
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Subject: Re: What causes this? Wed Oct 31, 2012 8:33 am

When the maff is unplugged..What does the computer do? does it just dump fuel to compensate? What im getting at is if the maff is functional but car runs great with it unplugged?

Subject: Re: What causes this? Wed Oct 31, 2012 12:38 pm

SuperRivL67 wrote:: When the maff is unplugged..What does the computer do? does it just dump fuel to compensate?

The computer resorts to calculating fuel and timing based on MAP (vacuum) and TPS readings. It's not quite as precise as MAF calculations from the factory.

When I get into advanced tuning, the first thing I do is unplug the MAF sensor and bring the fuel and timing tables to exactly where they should be so that the engine runs nearly perfect without the MAF sensor. With the MAF sensor the computer relies very heavily on that sensor's readings. Some cars that have converted to high volume turbo systems are flowing more air than the MAF sensor can read reliably, so it goes out of range. Those cars tune to run full time with no MAF, or get a much different MAF sensor working.

Subject: Re: What causes this? Wed Oct 31, 2012 9:37 pm

Swapped maf with one from a 98 3.8 problem solved. Now maybe I can put to use all the parts I've swapped out. Thanks for all the help I'm sure ill have more questions soon.