• Welcome to the Contour Enthusiasts Group, the best resource for the Ford Contour and Mercury Mystique.

    You can register to join the community.

MAF Sensor Screen - Don't Remove It !!!

I had this problem when I ran was tuning my Turbo. The MAF was throwin some retarded readings.

Joey recommended getting a screen and after that all was reading perfectly.

- amyn
 
so anyone know if any ford applications with the 80mm maf had a stock screen? where could i get one if there was?
 
crewchiefpro said:
It is not a filter, the Ford engineer posted that it is designed to straighten airflow around the heated wire. Removing it will cause incorrect MAF readings. I can tell you that on our Contours it will make a difference.

Auto companies don't spend money on parts unless there is a reason...
Click to expand...

Just a couple clarifications, its not so much smoothing airflow, but intentionally giving a bit of turbulence to EVEN out the airflow across the MAF opening so the readings are consistant, and it is most critical at low engine speeds, idle being the most obvious. Some cars run fine without it, some won't run at all without it, to everything in-between.

Some past posts on the subject...

http://www.contour.org/ceg-vb/showthread.php?t=47884&highlight=MAF+screen

http://www.contour.org/ceg-vb/showthread.php?t=28012&highlight=MAF+screen

And fwiw, I'd be interested in seeing the link Brett found that you mentioned. I don't believe I've seen the post in question, but I have a feeling its a guy I used to work with that spent some time in MAF design at Ford.
 
Rara said:
Just a couple clarifications, its not so much smoothing airflow, but intentionally giving a bit of turbulence to EVEN out the airflow across the MAF opening so the readings are consistant, and it is most critical at low engine speeds, idle being the most obvious. Some cars run fine without it, some won't run at all without it, to everything in-between.

Some past posts on the subject...

http://www.contour.org/ceg-vb/showthread.php?t=47884&highlight=MAF+screen

http://www.contour.org/ceg-vb/showthread.php?t=28012&highlight=MAF+screen

And fwiw, I'd be interested in seeing the link Brett found that you mentioned. I don't believe I've seen the post in question, but I have a feeling its a guy I used to work with that spent some time in MAF design at Ford.
Click to expand...

Here is the link.

http://www.sonicmach1.com/calibration_q_and_a.htm
 
Cool, that's all good stuff there. Not who I thought it was, but I did recognize the guy, we worked on different areas of many of the same projects at Ford.
 
I don't run one on my Supercharged Cougar running a blow through setup. The car never came with one from the factory. The car runs fairly well but has an occasional idle dip. It isn't stalling but it would be nice to get rid of it. I may give one a try next time I pull it out of storage.
 
BOTTOM LINE on MAF cars. don't touch anything on the intake unless you tune for it. they are calibrated to work with exactly what is there. if you remove a screen or what have you..... tune for it!
 
Blackcoog said:
I don't run one on my Supercharged Cougar running a blow through setup. The car never came with one from the factory. The car runs fairly well but has an occasional idle dip. It isn't stalling but it would be nice to get rid of it. I may give one a try next time I pull it out of storage.
Click to expand...

My cougar didn't have one either. I think I will get one and tune it in with my 3L.
 
TRicker said:
BOTTOM LINE on MAF cars. don't touch anything on the intake unless you tune for it. they are calibrated to work with exactly what is there. if you remove a screen or what have you..... tune for it!
Click to expand...

Personal experience with multiple vehicles tells me this is untrue. I've upgraded MAFs and TBs in 3 Mustangs without tuning and noticed a performance increase. I do have my current Cobra tuned but I ran it untuned with an A9L for awhile. I upgraded the MAF in my SHO with a Mustang MAF sensor in a 73mm C&L housing, didn't tune that and it ran like a champion. My CSVT also runs an aftermarket intake setup with no tune and no screen and its fine also. Still has the stock maf although I have a 65mm mustang TB from Haaaarrry still waiting to go on.

I don't know if I'm just really fortunate or what but I've never run into ANY of the issues people warn about when messing with the maf/intake tubing. It probably helps that I keep all my vehicles well maintainted and I do all my own work so I know exactly what is what.
 
ScottyDsntKnow said:
Personal experience with multiple vehicles tells me this is untrue. I've upgraded MAFs and TBs in 3 Mustangs without tuning and noticed a performance increase. I do have my current Cobra tuned but I ran it untuned with an A9L for awhile. I upgraded the MAF in my SHO with a Mustang MAF sensor in a 73mm C&L housing, didn't tune that and it ran like a champion. My CSVT also runs an aftermarket intake setup with no tune and no screen and its fine also. Still has the stock maf although I have a 65mm mustang TB from Haaaarrry still waiting to go on.

I don't know if I'm just really fortunate or what but I've never run into ANY of the issues people warn about when messing with the maf/intake tubing. It probably helps that I keep all my vehicles well maintainted and I do all my own work so I know exactly what is what.
Click to expand...


Very lucky. We run Turbo cars and it really affects our combination. It may not on yours but others on here may be having issues that this will help/correct. It is for info purposes only, use this info as you see fit.
 
crewchiefpro said:
Very lucky. We run Turbo cars and it really affects our combination. It may not on yours but others on here may be having issues that this will help/correct. It is for info purposes only, use this info as you see fit.
Click to expand...

Yeah, this is the thing, sometimes you get lucky and it all works great, and sometimes you don't and it runs like crap. Just like anything else you modify, be prepared to deal with it if it doesn't turn out quite how you hoped.

Some of the aftermarket MAF companies used to adivse people to rotate thier MAF to try to get it to work better. And to some extent this is true, by placing the sampling tube in a different area, you get a different velocity of air, which may correspond better to the average flow in the MAF vs. some other section. Still a hack way to go though, lol.

MAF changes have some other things going against them too, which further compounds matters. Aftermarket MAFs are generally known for not being as accurate or as consistant as an OEM MAF (there are exceptions) due to the sensor itself, and the layout of the sampling tubes. They also typically use a hack method of scaling the airflow as reported to the PCM, rather than recalibrating the PCM to the correct MAF airflow vs. voltage curve.

I guess the bottom line is that even MAFs aren't nearly as simple as people think, and just like any other modification, be prepared to do the development work on your own car if you want it to run right. The OEMs spend years and millions of dollars on every engine to get this stuff right, you shouldn't expect to get it right on the first shot when you change it all up with a $45 used aftermarket MAF originally intended for another car . . .
 
Rara said:
Some of the aftermarket MAF companies used to adivse people to rotate thier MAF to try to get it to work better. And to some extent this is true, by placing the sampling tube in a different area, you get a different velocity of air, which may correspond better to the average flow in the MAF vs. some other section. Still a hack way to go though, lol.
Click to expand...

My 80mm responded in just this way. Better idle in its current position vs the 180* rotation it was originally. FWIW, I plan to replace the screen this spring. Becuase of this post and links supporting it.

I'm willing to give up the .6 HP gained from removing it.(/sarcas
 
I had a crack housing so I replace my MAF with a metal one, I didnt add the screen back in because I thought thats what caused it to crack. The two mating surface didnt meet well. Is there a gasket that goes between the two? I remember it having recessed area on the MAF itself. I just dont know if my screen it right. Did anyone else notice a similar issue?

I have had the screen sitting in my kitchen waiting to go in since i first read this thread.
 
I had a crack housing so I replace my MAF with a metal one, I didnt add the screen back in because I thought thats what caused it to crack. The two mating surface didnt meet well. Is there a gasket that goes between the two? I remember it having recessed area on the MAF itself. I just dont know if my screen it right. Did anyone else notice a similar issue?

I have had the screen sitting in my kitchen waiting to go in since i first read this thread.
 
You must log in or register to reply here.
Back
Top