Replace MAF sensor and spark plugs

[sgupta]

Hi guys,

I have a 1997 nissan sentra gxe and am trying to do tune-up and servicing for the car by myself. I find this a very useful forum to get some information and suggestions and I hope this will be a naive question for everyone but I will appreciate any help.

For the past couple of months, since the onset of winter essentially, the car's gas mileage has gone down from 30 mpg to around 27 mpg (mostly city + a little highway driving) and I have a constant engine check light popping up.

I got the code checked from autozone.com and it turns out to be MAF sensor P0100. I have cleaned the sensor element and the surroundings using a MAF sensor element cleaner I got from Schucks and the electrical contacts into MAF sensor are clean too but am still having the engine light ON. I have also replaced the air filter just to ensure that its not because of that.

Will that leave the option of replacing the MAF sensor (around $200 at schucks) ? Is there a way I can try a spare MAF to check if the problem lies with the sensor element or its the electrical contact harness where its getting shorted ? I also doubt that the o2 sensor can be the problem since as mentioned in one of the posts my gas mileage is getting down.

I appreciate if anyone in the forum can share their experience.

thanks.

[nametakennow]

Bad gas mileage could be caused by a bad O2 sensor.

The MAF is integrated into that bit of pipe, so you can't just replace part of it.

You could use a voltmeter to check and see if electricity is getting all the way to the sensor.

[RED_DET]

Most cars do drop in gas mileage in the winter. But in your case with a cel, thats probably the case.

[sgupta]

How do we measure the voltage across the harness of the MAF using the voltmeter? If I try to plug out the MAF plug and measure voltages, the car if left on idle run stops.

I referred the service manual and they have mentioned to measure the voltage in the EC Module for which I have to open the front passenger center console. Is there some other way we can measure the voltage without using the EC Module?

Thanks.

[nametakennow]

I don't know of any shortcuts, unfortunately.

[nissan_4_life]

call nissan they should have a tool to check the MAF i had to have it done to my max