86RXseven

My 86 rx-7 second gen, wont stay running, fires up but it dies right away if i dont give it 1/2 throttle, i bought it less then 2 weeks ago. I havnt rallyed it or nothing. what ive been told is that it could be the mass air flow sensor, could some one please tell me how to test it or give any other ideas on what it could be. im sorry if this question has been answered a bunch of times but i cant figure out how to seach for anything on this forum so maybe just explain how to do that. sorry if im a idiot.

skatelement

pinouts of the plug on the snsor Fc E1 E2 Vref E2 Vs THAa

E2 to Vs = 50-500 ohms
E2 to Vref = 200-500 ohms
E2 to THA = intake air temp -4 deg f = 10,000-20,000 ohms
32 deg f = 4,000-7,000 ohms
104 deg f = 900-1,300 ohms
140 deg f = 400 - 700 ohms
press open the measuring plate inside resistance between E1 - Fc fully closed infinity resistance , fully open is 0 ohms
E2 to Vs 50 - 500 ohms fully closed and same open

86RXseven

im sorry but that did nothing but confuse me. is there any way you could break that down and explain it to me a little? just explain what i have to do to tell if this is the reason why my car wont stay running. thanks for the reply tho i just need a little more info. i heard you could test the MAF with a multimeter and tell if its good or not. this true or no? thanks

86RXseven

nothing else? man im really freaked out i just paid $2k for this car and it ran like a champ for 10 days exactly now i cant even drive it. wont even run unless i keep it almost floored is there any other ideas or suggestions/ways to test MAF? thanks...

InsomniacFC

iTrader: (4)

Check and make sure the plug on the MAF is on all the way. It's right under the air box. Mine came off one time and I had to get it towed home only find out I could have just plugged it back in at the Savemart parking lot and drove away.

Other than that, have you done a tune-up on it since buying it? Like plugs, air filter, fuel filter, and etc? I'd check the spark plugs and make sure they are not fouled as that will make it hard to keep running if they are clogged with carbon. My car would die at stoplights and be really hard to start when mine were bad. When you replace them make sure you get the plugs for an RX-7 (surface gap NGK's). They come in a pair's of trailing and leading plugs. Leading on the bottom row, trailing on top.

Also, get a Haynes manual for your car. The troubleshooting section in the front is a lifesaver.

1revin712488

what ^^he^^ said and make sure all of the hoses on the intake are connected.

hanman

We need more info.
You say it runs if you give it 1/2 throttle. Will it stay running? If so, it's not the AFM.
Does it only do this cold? Will it run once it's warmed up? If so, water thermosensor.
If it's a consistent problem hot or cold, maybe a good size air leak.
Have you done any engine work to it lately?

Chuck

iTrader: (2)

Typically, start and die problems can be linked to a serious vacuum leak. I would check all the vacuum lines (and there are a bunch of them). They get hard and brittle over time exposed to serious engine heat. Cracks can be hard to spot but still leak air. Vacuum leaks can also happen at the fuel injectors and the gaskets at the TB, UIM and LIM.

Malefoda

Our AFM is a VAF and not a MAF, isn't it?
Should test the fuel pump switch wich is in, check the FSM to see where it should make contact when the flap is a bit open.

Evil Aviator

Does it always do that, or just when the engine is cold?

You can see the free factory service manual in the FAQ. (The 1988 manual works for the 1986-1988 cars).

Mazda calls it an Air Flow Meter (AFM). Yes, it is a vane type airflow meter. Vane type airflow meters are a sub-set of mass airflow (MAF) meters. Therefore, MAF is correct, but AFM or VAF is more specific. I think it is better to use the MAF term on this forum so as not to confuse the engineering-challenged folks.

mike_merryguy

iTrader: (8)

mine did that after messing with the intake, i forgot to put the large rubber hose back on the bottom of the main intake, check a few inches out the bottom right by the throttle body make sure that tube is connected

like the other guy said this caused a serious vacume leak

Jedsterama

The car's still under the implied 30 day warranty.
Take it back and bitch.

HAILERS

YOU go to the Airflow Meter, and make sure its elect plug is connected. See the free online FSM if you don't know what the AFM is or its location.

Then again, like the man above said, the fuel pump would not run if the engine started and the key was returned from Start to On, and the elect plug was off the AFM. So I just wasted my time typing the above.

So you could pull the airfilter off the AFM, turn the key to ON, and push aft on the vane at least a half inch or so. The fuel pump should run if you do that. You should be able to HEAR the fuel running thru the fuel rails as you hold the vane aft.

IF you hear the fuel pump, then it sounds like there is a LARGE air leak as in a LARGE hose off the intake area.

You can follow the instructions given by OTHERS above and check out the AFM per the instructions in the FSM. The Fuel and Emissons section has it. You NEED a digital meter.

A simpler way to check the AFM is to go to the AFM input at the ECU and backprobe the wire from the AFM to the ECU. Just turn the key to ON while backprobing the wire at the ECU, with the meter to dc volts. Have someone push the vane in the AFM slowly aft while you watch the meter. The voltage should slowly go DOWN from approx 4.5vdc to approx a half volt when the vane is fully aft.

This thread sounds more like someone that has no fuel in the gas tank than any of the above in my humble opinion.

Malefoda

Isn't a MAF a thingy like the S13 or such AFM?
Ok won't help him, I stop

86RXseven

this is exactly what it was i figured it out yesterday car runs fine now... sorry im a idiot

mike_merryguy

iTrader: (8)

FTW... lol
yea i was an idiot too cause i was checking everything but that tube and i was sure i hooked it all back up the right way...