itsmeboosted

I Have an 86 rx7. The engine will start and rev to about 3,000. Then cut off after about 5 seconds. Does anyone have any advice on what could be the problem? The car ran fine before i drove it into the building about a week ago.

misterstyx69

iTrader: (142)

Is your AFM(air flow meter) hooked up?(connector plugged to it?)..if not the car will start and die
if not,Plug it in and it should be fine.

68Sniper

iTrader: (1)

Could be a fuel filter? cheap fix if it works

itsmeboosted

Ive replaced the filter. and the mass air flow meter is connected, but the connector doesn't seem to snap in like my previous cars have. I will check the filter and make sure it's not defective. I work at a local part store and i do see new parts being sold that are deffective. thanks for the tips so far!!

itsmeboosted

I also checked the fuel pressure and i have 37psi of pressure coming out off the fuel filter, and the fuel pump is brand new.

NewRXr

Throttle position sensor went out? Check it. Hold the throttle open with one hand and pop the TPS up and down. Sometimes that will clear them up if some corrosion has built up on the potenimeter inside.

Vernon

RTRx7

iTrader: (2)

It's your afm. Get a new one.

HAILERS

Jumper the two socket fuel pump check connector. Key ON. Listen for fuel going thru the fuel rail. IF you hear fuel in the rail, then start the engine.

Your bypassing the gnd signal from the afm to the circuit opening relay when you do this. The circuit opening relay will pull in and make the pump run even if the switch inside the afm is not working.

It could also be just a large air leak somewhere.

itsmeboosted

where exactly is the connector i'm needing to jump?

HAILERS

Yellow in color, two sockets and not mounted to anything but floating around in the EM harness near the rigth front strut tower. Close to the boost/pressure sensor area. Might have a black boot surrounding it.

It's circled in purple in the attached jpg.

itsmeboosted

also..shouldn't the fuel pump turn on when i turn the ignition to the on position? I have no fuel pressure with the key there unless i have tried starting the car.

satch

iTrader: (1)

Start yes, key to on no. This is changed as suggested by Hailers when you bridge the two terminals in the fuel pump check connector. When bridged it will pump with key to on otherwise it won't.

Pele

iTrader: (28)

I had this happen. It's the circuit opening relay in my car.

https://www.rx7club.com/showthread.p...+opening+relay

itsmeboosted

ok, so if it works with the jumper then what is the problem and how do i fix it?

HAILERS

Well, let us know if the engine keeps running with the jumper in the fuel pump check connector or not.

If the engine now stays running, then for one reason or the other the fuel switch inside the afm is not *making* when the vane of the afm moves aft. All your doing when jumpering the two socket, yellow fuel pump check connector is duplicating what is normally done when the vane of the afm moves aft more than ??? 18". You putting a ground on the circuit opening relays coil to pull that relay in to keep the fuel pump running.

The circuit opening relay has two coils either of which will pull the relay in and make the pump run. One coil is controlled by HOLDING the key to START and the other coil is controlled by the afm's vane moving aft at least 1/8" and putting a gnd on that coil.

If you jumper the yellow two socket fuel pump check connector, and the fuel pump does not run with the key to ON, then the circuit b/t that yellow connector (and the afm's internal switch) is open to the circuit opening relay.

The gnd for that yellow connector and the gnd for the afm's switch is the same identical gnd and is spliced to the ECU gnd point on top of the rear rotor housing.

itsmeboosted

I did the jumper and the fuel pump turned on with the key in the on position. however the car started then died once more.

HAILERS

Big air leak...............or bad afm..............or

Can you MAKE the engine keep running long enough for the water temp to get fully hot? Then see if it'll idle?

Anyway, for sure it's not the *fuel* switch inside the afm not making. Is the electrical plug on the afm?

On the large duct that goes from the afm to the throttle body......there should be a plastic nipple on the bottom of it with an approx 1/2'" hose on it. Is that hose on the duct and is that hose connected to the metal pipe that runs on the aft side of the throttle body?

On the left rear side of the engine. There are a couple of 1/2 inch hose there. Are they alll conencted up to where they should go?

Does the BAC on the left side of the engine have its approx 1/2" air hose on it and the other end of that hose connected up to where it goes?

itsmeboosted

They're are 2 lines that are cut, one is aprx 1/2" and the other is aprx 7/32". Other than these to lines i seen nothing out of the ordinary other than i need to tighten the alternator belt. Also..where are these wires supposed to go?

HAILERS

The large intake duct B/T the air filter and throttle body have to be installed for the engine to start. On the bottom of that large black duct is a smaller hose I show in RED in the attachment. Is that hose on the bottom of the large duct and is the other end of it attached to a metal tube that runs on the top rear of the engine as shown in RED in the jpg attached.

And on the rear left of the engine, do you have the hose that are colored in BLUE installed?

I couldn' t figure out the hose in your picture.

itsmeboosted

The red one i have and it is installed correctly. the blue i'm not sure about. I'll check on that tomorrow.