FEOA Forums banner

mass air flow sensor

4K views 37 replies 10 participants last post by  juggalo 
#1 ·
i just got one yesterday from a 94 escort lx just cuz it's bigger than the one i had in my 92 wagon. i put it in, runs great on the streets but when i'm on the freeway it feels like the ignition timing retards. i know i can get a throttle body from the 2 liter motors. would that help?
 
#3 ·
actually, you need to get the ECU that matches that MAF sensor housing's flow characteristics.

i've also done the swap. i got the ECU on 1/2 price day at the pick-a-part, and it was only $15! :)

before switching the matching ECU in, the car pinged like a mofo at higher revs due to running lean.

the better-breathing MAF housing causes the MAF sensor output voltage to be lower for a given RPM and it gets worse as the revs get higher.

this causes the original ECU to think that less air is going into the motor than really *is* going in, and it meters the fuel according to what it thinks is going on, rather than what's really going on, making it lean out something fierce

the '94 ECU will work nicely, and if you don't have EGR hardware on your car, get the EGR solenoid and sensor off the firewall with the ECU, since it's necessary to avoid the check engine light, and trivially easy to hook up and fool the computer into thinking it's really working.... :)

it's worth the effort. the later ECU has a better program, along with a couple extra degrees of timing to go with the EGR. my car had no EGR from the factory, so i run 89 octane in the summer to take advantage of the extra timing.... throttle reponse in mid-band is better. gas mileage is about the same as before.

HTH!

c ya,
dutch
 
#4 ·
it is the housing for the MAF sensor. i put my old one back in and no more lagging on the freeway. i think i'd have to get a high output coil pack and a fuel controller before i put it back on. i tried reseting the ecu and no change. i even tried using MAF sensor cleaner and nothin.
 
#6 ·
problem solved. the reason y it was surging is cuz it was runnin lean with that much air flow. i talked to the tech at escortfocus.com and he said to disconnect the air temp sensor. i did that and no surging. WOO HOO!
 
#7 ·
I'm still thinking it's because of what Dutch and others have said. You're using a MAF that's calibrated one way with a computer that's calibrated a different way. The computer's getting confused, and causing the engine to not run correctly.

Disconnecting the air temp sensor is causing the computer to guess, and its guess will usually be toward the rich side. It will run better, but it may set the check engine light, and not run as efficiently as it should.

Casey
 
#8 ·
i had no problems after gettin off work with a 20 mile drive home doin 75+
 
#10 ·
white-lightning said:
You needed the whole maf sensor and all, that is why it ran like crap.
it ran like crap on the freeway with both sensors on that housing so it didn't even matter
 
#11 ·
i think i know what the problem could be. the new fuel pump that i picked up from schucks and intalled it 8 months ago whines around a quarter tank and goes w0w0w0w0w0w after it's been restarted so i think it's not pushin out enough pressure and needs to be replaced again. thanks for the help.
 
#13 ·
lol. ok i'll start listenin to yall instead of the tech at escortfocus.com. thanks
 
#14 ·
juggalo said:
lol. ok i'll start listenin to yall instead of the tech at escortfocus.com. thanks
There are 16,000 members here, of which several hundred are SAE or Ford Certified technicians who actually make their living with tools, pinpoint troubleshooting charts, and electonic diagostic devices in their hands. But not a single one of us is going to be right compared to the guy that EFP calls their "tech". But I suspect you are mis-understanding him as well because you do not seem to understand the big-picture relationship between the MAF housing, the hotwire assembly that's in it, and the transfer function logarithm of your cars computer (AKA programming). Change your computer to match the MAF you selected or put your original MAF back in BEFORE attempting to fix a problem that you may have caused yourself.
 
#15 ·
juggalo said:
lol. ok i'll start listenin to yall instead of the tech at escortfocus.com. thanks
from what they told you, their tech seems to be as talented as their website designer.

taking out the air temp sensor is a bandaid fix. the ecu will add more fuel when you do this because it has to play it safe and assume you are in subfreezing weather and need the extra fuel. this helps with your lean issue that the bigger maf is causing, but you are still just beating the bush around simply going and grabbing the matching ecu and not having to play the "unplug a sensor game".

no reputable company would tell you that unplugging that sensor will fix your problem. they might tell you that it would help, but it is not the proper solution.
 
#16 ·
ok, i'll just run with the sensor disconnected till i get paid. thanks.
 
#17 ·
i just found out runnin it with the air temp sensor disconnected for a while makes the fuel pump act like it's fittin to take a fatty shit
 
#18 ·
I did the later maf on my 1.9 back when I was an idiot in college and noticed the lean freeway issue, so I put my engine back to stock and guess what I had MORE power than with the big one, adding bigger things is not always better, you can put the biggest air filter, biggest piping, biggest maf body, biggest throttle body you want on there, it won't make ANY difference on the 1.9 because the intake valves and whole head is very restrictive in it's flow design! you have to port and polish the heck outta the head, then get way oversized valves for any of your mods to work man.

like I said save yourself the headache at pull a part and go BP! motor and trans at PAP will run you about 200 and you'll be happy with the power output of it stock. save up some money and make it happen instead of playing with the 1.9

with that being said I don't hate 1.9's they're GREAT economy motors, just not power houses unless you put a lot of time and money into them. and also really reliable too.
 
#19 ·
Escort92Man said:
save yourself the headache at pull a part and go BP!
Actually, an SPI swap would be much less of a headache for him than a BP swap.
 
#20 ·
dude I didn't even think about the SPI swap lol, you're right matt! a little wiring with the SPI instead of a headache to swap harnesses and computers yeah!

mmk juggalo time to PAP up a SPI for yerself! ha ha.

I guess I just fell more in love with the BP's, they pull so stinkin hard it's nice! I do however like the sound of a 1.9 cruising better with a good deep muffler and the gas mileage is a bit better in the 1.9's :D I'm squeaking 34ish outta my BP right now running semi lean it's nice.
 
#21 ·
i'm in the middle of doin the 2.0 TB swap. i just wish i knew where my drill bits were so i can make the mounting holes bigger. the wires for the TPS matches on both connections but i spliced it already since i didn't wanna rick damaging anything
 
#22 ·
but I don't think the 2.0 TB is going to help you out much man, maybe 5 hp max in the upper end but idk man. but if you think about it putting a bigger throttle body on the small intake is like putting a bigger funnel infront of a small funnel already, it isn't gonna flow more it can only flow what the small funnel can flow. try it and see though it's all you can do.

see this is why I love BP lol, don't have to do these swaps, eventually I'm going to do a full cold air intake and a pacesetter header and upgrade my exhaust to a nice 2.25 inch with my otto racing muffler, that's all I need right there it'll hit 100 I know for sure, even 120 and I will never take it that far so I'm good ha ha.

best of luck with it though but like others said juggalo bandaid fixes only last so long, eventually you could end up hurting the motor running it lean or frying something man, like you said your fuel pump is getting loud, not good stuff dude.

I'd say till you get everything to make it all run good go back to stock settings and play it safe!
 
#23 ·
Escort92Man said:
but I don't think the 2.0 TB is going to help you out much man, maybe 5 hp max in the upper end but idk man. but if you think about it putting a bigger throttle body on the small intake is like putting a bigger funnel infront of a small funnel already, it isn't gonna flow more it can only flow what the small funnel can flow. try it and see though it's all you can do.
people r now goin with the 3.8 TB which really needs the intake ported. i don't have the tools or money to get it done so i went with the 2.0 TB.

Escort92Man said:
best of luck with it though but like others said juggalo bandaid fixes only last so long, eventually you could end up hurting the motor running it lean or frying something man, like you said your fuel pump is getting loud, not good stuff dude.
i have a warante on my fuel pump so if that goes i can go get a new one fore free. and the leaning problem is y i got the PCM yesterday. i think everything will come together nicly.
 
#24 ·
The 2.0 TB is 4MM bigger and the manifold will still need to be ported. You will actually loose power and end up with a flat spot if you don't port the manifold. A Dremel and one of these bits are all you need. http://www.dremel.com/en-us/Attachments ... px?pid=115

Please don't throw stuff together without doing all the steps, you will just end up wasting time because you will end up having to do it over again.
 
#25 ·
i'll see if they have them at harbor freight tools tomorrow then. will the 3.8 TB be better than the 2.0 or will that cause some problems since i'm still runnin the stock exhaust system?
 
#26 ·
I personally did the 3.8 throttle body on my heavily ported and polished 1.9 with the big maf body, I noticed I had more low end power but sucky high end power. I have the WHOLE kit if you want my 3.8 throttle body man, I'll sell you the whole kit for like 10 bucks, that's a steal I made a custom throttle cable bracket, cleaned the TB good, made it so the throttle cable hooks up on the TB, took me about 2 days to make all the stuff so if you're interested lemme know, and the TPS on it is good. the problem I had with it is I was running the big maf body with out the upgraded PCM so it didn't work for me, if you are interested in the 3.8 TB though it'll bolt right on and hook right up dude. just sitting collecting dust in my garage. oh and the bracket was fun to make I drilled a whole in my leg it was so fun! lemme kno dude PM me or myspace me!
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top