ReaperFC3

iTrader: (4)

i own a 1987 mazda rx7 s4 NA and when i turn it on it idles fine, but when i rev it, it goes a lil bit slow, and when i took it for a drive it seems its lost some power what could be the problem im new to the rotarys engine oh and my Mass airflow sensor i here something flapping inside of it when i rev it? thanks for the help

RotaryEvolution

iTrader: (30)

take a video if possible so we can hear it. the AFM shouldn't be pulsing like that unless there is a large vacuum leak or the engine is misfiring due to timing or compression issues.

AGreen

iTrader: (11)

Sounds like the spring in the MAF sensor broke. If it's broken, the flapper is opening too wide when it shouldn't, making the mixture too lean. Not enough fuel, throttle wide open, engine revs slow.

Pop the sensor out (remove the air duct and air box). Hold the sensor in your hand, and move it all around. If the flapper doesn't stay shut, the spring's broke. Get a new one and your problem is fixed.

But like the Karack said, all of that other stuff can cause slow revving as well.

ReaperFC3

iTrader: (4)

ok i check the spring is not broken, and how could i tell if were is the vacuum leak cuz i do here some hissing noise? like i said im a newb. thanks for the help

AGreen

iTrader: (11)

Brake cleaner, or throttlebody spray. Even MAF cleaner. Spray it all around the intake, intake manifold, etc. If the idle smooths out, revs up, sounds different, you've found the leak.

ReaperFC3

iTrader: (4)

oh okay thanks know i have to wait for the rain to smooth out cuz it hasnt stop raining for 4 days know and i dont have a garage but thanks alot for the help

ReaperFC3

iTrader: (4)

okay i spray it and nothing couldnt find anything, could it be the timing? how could i time the car?

KompressorLOgic

iTrader: (6)

cloged cat converter?

ReaperFC3

iTrader: (4)

hmmm never tought of that let me check and ill tell you guys if it was or not

AGreen

iTrader: (11)

An easy way to check if the catalytic converter is clogged is to hook up a vacuum gage to somewhere on the intake manifold. If it is clogged, you should be able to see vacuum creep towards a pressure when you quickly snap the throttle open and shut.

ReaperFC3

iTrader: (4)

ok thanks man

FelixIsGod29X

iTrader: (50)

If the cat turns out ok then check for codes. There's a write up using 2 LED's from radio shack for under 10 bux to check for codes. Can also be used for TPS adjustment.

EDIT: Here's the link

http://fc3spro.com/TECH/HOWTO/ERRORC...KI/zerror.html

ReaperFC3

iTrader: (4)

Thanks Man ill gotta go to radio shack if that cat turns out to be ok

Amur_

I'm surprised no one suggested the air filter might be full/clogged and needs to be replaced.

ReaperFC3

iTrader: (4)

lol oh **** i gotta check that that would really suck if it was that lol

HAILERS

Sparkplug wires installed on the wrong sparkplugs? Trail sparkplug wires crossed up?

ReaperFC3

iTrader: (4)

ok its not the cat or the air filter, lol hmm u really think its the wires?