no mafs, car idles perfectly. with mafs, idles like me shite

[Andrew Bohan]

so i had my intake off, and i had to move the car real fast so i moved it without the intake on and it idled perfectly. like brand new.

so i went and grabbed the intake and plugged the mafs in and it started bogging and wanted to die.

i let it idle for a few minutes without the mafs and got out to check things out (i wasn't ever able to do this before since i had to always be giving it gas for it to stay alive). there was so much white smoke coming from the exhaust (!!!!) and it smelled like gas. fun times eh?

so do you guys thing there's a problem with my mafs or what?

[240Stilo]

Yes. Try out another one. Did you try to drive it without the mafs?

[Andrew Bohan]

i drove around my apartment complex with it off. can't rev above 2500 of course, but it doesn't stumble at all!
i'm gonna try another one as soon as i can. hopefully tonight

[autobahNESSA]

if u cant find one i got my DE maf that you could use to test

Of course you'd need to come to milpitas to get it.
you coming out to the Qcup meet?

[Andrew Bohan]

yeh man, bring that shit!
how much you want for it? and i'm sellin it back to you if it doesn't fix my problem mmmkay?

[kazuo]

Drew,

sounds like my exhaust right now. My fumes arent totally white, but they do smell like super duper richness.

Check the ECT (Coolant Temp) sensor. It's over near the thermostat housing. If that thing is wonky it'll make ya run rich. I need to check mine.. bleh

I told you last night Chris had a DE MAF. :P

[Andrew Bohan]

okay i'll check ect.

how come chris doesn't have a lp style banner? why you hatin'?

[kazuo]

how come chris doesn't have a lp style banner? why you hatin'?

He didn't ask for one.

No ask, no get.

But he did ask me earlier so I guess I'll cough one up.

[Andrew Bohan]

He didn't ask for one.

But he did ask me earlier

omg you flip flopper i'm not voting for you

[nightwalker]

it's not that hard man. You're MAF is fried. Kaput! Dead! Gone to MAF heaven! I'm 100% sure on that. Just get another.

[Jeff240sx]

it's not that hard man. You're MAF is fried. Kaput! Dead! Gone to MAF heaven! I'm 100% sure on that. Just get another.
+1.
That is the test for a bad maf. Remove/unplug it, and run the car. If the issue goes away, it is the maf, and replace it with a new/new-to-you unit.
On a side note, use PMs, don't crap up a thread.
-Jeff

[Andrew Bohan]

okay i got chris' maf. now i'm going to bed. will update tomorrow

sorry about crapping up the thread :kiss:

[Andrew Bohan]

new maf didn't help!!! oh noes! now what?

[The Hamsterball]

Try cleaning the connectors with electrical connection cleaner spray.
Just shower both ends with it.. let it dry after use.

then re-plug.

just a suggestion of something you can try..

[Var]

+1.
That is the test for a bad maf. Remove/unplug it, and run the car. If the issue goes away, it is the maf, and replace it with a new/new-to-you unit.
On a side note, use PMs, don't crap up a thread.
-Jeff


what if when you disconnect the MAF the ECU automatically goes into a "limp mode". It could be running off some default setting therefore ignoring all sensor input. He already changed the MAF and it made no difference. It could be other sensors or maybe the connection like said above

[Phlip]

And for the record, according to what I take from everything I have read, aren't you supposed to disconnect the battery everytime you disconnect the MAFS?

[Var]

And for the record, according to what I take from everything I have read, aren't you supposed to disconnect the battery everytime you disconnect the MAFS?
i think so..you're supposed to disconnect your battery every time you do anything that's connected to the ECU.

[idlafie]

new maf didn't help!!! oh noes! now what?

Try checking your air filter / air filter box. Check to see if there isn't a plastic bag or something wrapped around it or clogging it up. IF the air filter/air box is clear, then check your IAV valve..you know the one that regulates your idle. Take some carb cleaner to it....it might be dirty. Also check the OTHER air regulating valve...the one that's on the driver's side by the exhaust manifold. Check to see if that hose is still intact. If none of that works, then put your ECU into Diagnostic Mode & see what DTC codes your engine is kicking out.
You sure you don't have a vacuum leak somewhere??
Anyhow, good luck with the repair.
ID
'95 SE

[Andrew Bohan]

i have no intake attached right now, it's just straight throttle body, so there's no clog or anything.

swapped coolant temp sensor like was suggested, didn't help.

vacuum is about -15 inches Hg. does that sound normal?

guess i'll go check for codes. i'd been getting 55 before i discovered it ran fine without maf

[Muzzy]

that number sounds low..mine is usually at 40hg...although i have an SR...idk wut u have. sounds like a prob i had b4. when i started to boost(2500rpm) it would bog like a mofo. my MAF was gettin too hot i was told. so i made a heat sink. and that cured it. i dont think this will solve your prob if it snot near a big heat source or somethin. but..check for continuity(sp?) and voltage and crap in the maf to see if it is bad.

[Andrew Bohan]

update:

okay i went back out and checked the ecu for codes. it was throwing 12. i thought, well maybe that's cuz of the maf being unplugged. i i disconected the battery and made sure the maf was hooked up right, and started the car...

and it idled!

:w00t: :w00t: :w00t: :w00t: :w00t: :w00t:

checked the ecu again and it was throwing 55. hooray for my car.
now all i gotta fix are the coolant and oil leaks, and then it's off to the tuning shop.

thank you everyone!

[autobahNESSA]

So you dont have to burn the car anymore? Tite, so my ecu and maf fixed it?
tune it so next week you can roll down with it.

[autobahNESSA]

"Quote:
Originally Posted by kazuo
He didn't ask for one.

Quote:
Originally Posted by kazuo
But he did ask me earlier


omg you flip flopper i'm not voting for you"

ya ART where is my banner? BAD leader bad leader!

[Andrew Bohan]

yargh. i tried to drive and it started doin the same shit. this is using chris' ecu. and my maf. tomorrow i'll try again with chris' maf.
maybe i just have to get it idling and i can adjust the safc from there...

[Jeff240sx]

what if when you disconnect the MAF the ECU automatically goes into a "limp mode". It could be running off some default setting therefore ignoring all sensor input. He already changed the MAF and it made no difference. It could be other sensors or maybe the connection like said above

What if monkeys fly out of my ass? It's not happening. The ECU DOES go into a default setting and makes the car run. When you plug in a maf, it overrides the default setting, whether it's good or bad. So removing a maf and it curing issues = bad maf. I don't have an explaination for why it suddenly got cured, and wasn't cured with a second maf, but I'd guess connection or the ecu needed a resetting (battery removal).

From Muzzy:
that number sounds low..mine is usually at 40hg...

40 in Hg = theoretical -19psi. Perfect vacuum = -14.7psi at sea level.
Your gauge is broken or you are wrong.
Full vacuum should be 28 in Hg, but I've never seen it. I run 22 in Hg
-Jeff

[Andrew Bohan]

so i went and swapped chris' maf back in and tried to start it and...


dead battery.

all those times starting and hardly any time running. luckily i got my cheapo battery at walmart so i can just trade it for a new one. this is the 4th battery i've gotten in about 5 weeks hahahahaha.

so i went back home, put the new battery in and it started.
then i played with the safc. bumped it up to +50% at 1000 rpm and started backin it off until the car wanted to die. now it's set at +45% at 1000 rpm and decreases from there. the car idles at 1100-1200 rpm (for now anyway) and my vac pressure is -14 in hg (-7 psi)

my crappy a/f gauge reads so lean that no leds light up. if i rev the motor it'll get onto the leanest led and keep climbing, but at 0% throttle it's off the gauge.

well i'm happy it idles with the intake on and everything. i guess i'll go for a test drive after laundry

:rawk:

[Var]

What if monkeys fly out of my ass? It's not happening. The ECU DOES go into a default setting and makes the car run. When you plug in a maf, it overrides the default setting, whether it's good or bad. So removing a maf and it curing issues = bad maf. I don't have an explaination for why it suddenly got cured, and wasn't cured with a second maf, but I'd guess connection or the ecu needed a resetting (battery removal).

[/b]




what i meant to say Fucky McFuckton, was that maybe if x sensor was bad and you disconnect the MAF, then the ECU stops reading the signal from x sensor and starts running normal.

[Muzzy]

Jeff- ??? wut??? thas wut it reads at idle and like 55 when i let off the gas and cruz in gear.

idk if it makes a diff but i have an SR and i using my turbo timer as my boost gauge(blitz). driving is like 25-15.

[Andrew Bohan]

okay i went drivin. w00t!!!11one
it's much stronger than my old motor. didn't die once. after it was warm it idled at 1000 rpm. then it got hot and i had to stop. oh yeah, my e-fans aren't all the way hooked up yet. water temp was 240º hahah yeah....

anyway, it appears to be going okay. just gotta fix those leaks and it's off to racetune.

[nightwalker]

for future reference guys, instead of disconnecting the battery and waiting, just touch the negative and positive terminals (off the battery) together, and everything will be wiped blank.

[Jeff240sx]

Jeff- ??? wut??? thas wut it reads at idle and like 55 when i let off the gas and cruz in gear.

idk if it makes a diff but i have an SR and i using my turbo timer as my boost gauge(blitz). driving is like 25-15.

If you're trying to make the statement that an SR sucks more than a KA, this is pretty good. Other than that, 55in Hg is 200% total vacuum, which is impossible. You're not understand that. You gauge is not reading inches of Mercury (in Hg), or you aren't reading it correctly. 200% total vacuum.. hahaha.
-Jeff

[Jeff240sx]

what i meant to say Fucky McFuckton, was that maybe if x sensor was bad and you disconnect the MAF, then the ECU stops reading the signal from x sensor and starts running normal.

And what I meant to say, you arrogant piece of shit, is that disconnecting the MAF sensor WILL NOT throw the entire car into a default mode. Simply default fuel maps to 2500rpm. This is why testing a MAF is done by disconnecting it.
-Jeff

[Var]

haha good show. that's why i'm PINK now!

[Andrew Bohan]

hey you got unbanned! that was a quick 3 months

now your name matches your car

[Muzzy]

ok jeff...its not 40hg its 40cmhg...does that clear this issue up??

[Andrew Bohan]

40cm = 15.7in. sounds good to me!

[statik]

hmm, im having a similar issue, the car runs like SHIT, motor shakes horribly. I disconnect the MAF and the idle jumps up to like 1k but it feels smooth. If i dont floor it and just rev it to 2500 its kinda boggy. Sound like a bad maf as well?