iceman2k

Hi, when i bought my car the MAF was out, i mean, it didn't have one, and i replaced it yesterday. The thing here is that i felt some changes, which i want to know if they're right.

1.- The rpm's dropped a little bit, i would say from 1000 (normal operation) to 850-900.
2.- The temperature gauge raised to the middle (before it was almost at the lowest level).
3.- When i start the engine i hear some whistling sound like if u r drilling something, what the hell is this??????
4.- The thing that i feel more important is that the SERVICE ENGINE SOON light that was on all the time too turned off but as i drive, i gets on and off from time to time.

Hope u can help me to be sure how bad or not are this changes, everything else was better, lightly stronger engine, engine feels smoother, less noise and better transmission changing.

Phate

Everything sounds right except for #3, I have no idea what you are talking about unless I hear it.

And about the SES light, take it to a parts store and have it scanned for free, and tell me what codes you are throwing and I can give you a better description.

FORCE_FED_Z

Without the MAf, the engine will go into a LIMP mode. It will still run but use the MAP sensor as a way of measuring the air.

As far as the whistling goes, I would say that it is probably related to the MAF somehow- try and pinpoint where the noise is coming from.

And assuming that your car is 96 or newer you will be able to get ti scanned. Otherwise most stores won't have the proper code reader.

iceman2k

oops i have a 94, let me continue doing the checking, i'll tell u later. I'm gonna visit the mechanic that sold me the MAF, maybe he'll give some advice too. Thankx Phate and Force!!!

NoRiceInside

if there was no MAF, wtf was there? open intake no filter? and the whistling is probably your smog pump. my guess is without the MAF youre in what joe descibes as LIMP mode, so the pcm doesnt bother running the emissions junk.

and how did it even run before? my car wont run with the MAF unplugged.

FORCE_FED_Z

The "whistling noise" Caleb is referring to should come on when your car is at idle- if you rev it slightly you should hear it go away, then come on again when it comes back to idle. Its your air pump kicking on-

The OBDII cars I think for emissions purposes won't let it run without the MAF.

And if your car wasn't running the emissions stuff, its very likely that something is a little gunked up.

For future reference- If you have a laptop, you can easily check your codes with your computer. Go to AKM Electronics and buy a connector cable. Then download the free program called "Freescan" and then using your laptop you can monitor everything your computer is seeing. It was one of my most valuable investments. Everytime the light comes on I know exactly what it is instead of having to guess or count the light flashes...

Phate

Only the OBDII vehicles wont run without a MAF. And even OBDII cars will run with a messed up one.

sman

Can you do this with a ODBII car?

97z2801ss

the going on an off light maybe an o2 sensor aswell, Thats what happend with the gfs Monte Carlothe light came and went.

Did you replace it with an aftermarket or OEM Maf?

iceman2k

We took the MAF from a good condition 95 camaro, it's a stock MAF. To answer the other question, before there was just no MAF like if u take it off and conect the filter. The car showed no big problem, i guess just much more gas consumption. What do u guys mean by LIMP mode????

Sinister95Z

As described above, the PCM resorts to a different way of running your car. Instead of using the MAF sensor to monitor the incoming air, it uses the MAP sensor. The PCM also stops performing certain functions that keep it running smoothly but are not necessary in order to keep the car operational. It does what it can to "limp" you home in the case of something breaking. Think of it as if you broke your leg while walking down to go get the mail. You would work through the pain and do what it takes to get home in order to fix the problem for good.

Did you make sure to reset the PCM after you made all these changes? The PCM needs to be reset after making any major changes so that it can sense and recalibrate for the new hardware.

iceman2k

I went to a repair shop and got my car scanned. It's the first time i do that since i bought the car, so it came with 9 codes but after they did reset the computer just came a 41 code (DI control circuit). The problem is that it keeps doing the same (SES light coming on and off), Functionally there's no problem.

FORCE_FED_Z

I'm sure there is software out there that will do the same thing, but the program I was referring to was actually written by a guy with a Lotus Espirit, it just happens to work for the the early LT1's and some late 3rd gens....