midnightbluefc

iTrader: (19)

okay i had this issue for a while now i thought it was a faulty mass airflow sensor, but now that this other one i got is starting to the same now!


its a 10th ae with a streetport and 680cc secondaries, porter wastegate, turbo back trust exhaust...


i noticed the issue when i turned the ignition on and i heard the fuel pump turn i looked into the engine bay to see id the yellow fuel check clip was jumpered and it wasnt.. so if the car is with the keys and ignition in the Accessory positing the fuel pump sends fuel AS IF THE CLIP IS JUMPED!

so i unplugged the MAF and the fuelpump stopped sending fuel, made my stereo turn off and quickly turned on (made my antenna roll back down for a little and went right back up)like a short...

this happened after I took my car to get an alarm installed ive looked at the steering column wiring but nothing out of the ordinary... any help would be appreciated thanks.

satch

iTrader: (1)

You state that at first that the fuel pump works w/the ignition "ON" and then you say it works w/the key to ACC. Which is it? One thing to check is the Fuel Check Connector which has two wires and one of the wires is Brown and "should" have voltage w/key to ON, engine not running. Also, the Black/White wire at the Circuit Opening Relay should have voltage w/key to ON or start but not when in the ACC position. And the Circuit Opening Relay could also be stuck in the "relay" position although all other possibilities are more likely.

AGreen

iTrader: (11)

Sounds like the shop that installed the car alarm used some power sources that share a common path with the fuel pump, and it's feeding power back into the fuel pump circuit somehow. Generally when an idiot installs something electrical, he'll grab a test light and find out what's got switched power at a convenient spot. He never looks at wiring diagrams.

midnightbluefc

iTrader: (19)

the key is in the ON position my bad. and i will have to disect the car even more thoroughly, i will inspect the fuel pump wiring... thanks.

midnightbluefc

iTrader: (19)

the thing is with wires to check i know i have the furl pump relay right under the dash above the gas pedal? but which ones should i check?

satch

iTrader: (1)

The "fuel pump relay" is the "circuit opening relay" so that means to check the B/W wire in the top row middle pin.

Post #166 has a pic of the relay located to the right of the steering column.

https://www.rx7club.com/showthread.p...epotato&page=7

EDIT: If the pump is thus working w/key to on then the most likely scenario is the Brown wire at the check connector, which is supposed to have voltage w/key to on but doesn't, and that would cause the pump to turn on, and it would take all of ten seconds to check the Brown wire for voltage w/key to on to verify whether this was the cause or not. If the Brown wire does have voltage w/key to then the problem is caused by something else such as the Black/Red wire in the upper left corner of the circuit relay has voltage w/key to on when it is supposed to have voltage only w/key held to start. Checking this wire for voltage also takes but a moment to do.

midnightbluefc

iTrader: (19)

aight thanks i kinda figured, but other than that which other wires should i check wiring is kind of a task for me, which wire is the ACC & the Constant to check the work that was performed on my car...

HAILERS2

The AFM will put a ground on the brown wire that runs b/t the AFM and the Circuit Opening Relay and that causes ONE of the TWO coils inside the Circuit Opening Relay to pull in and psss power on to the fuel pump............on a series four car.

So suspecting a bad AFM makes sense.............and that didn't fix the problem when replaced.

What throws me off is the antenna going up/down. It takes a ground from the radio assy to the antenna relay to make that happen. I don't see the tie in b/t the brown wire of the AFM and the gnd wire from the radio to the antenna relay.

That brown wire b/t the AFM and circuit opening relay does the same thing as what you do when you jumper the yellow two socket fuel pump check relay. When you jumper the yellow plug you put a gnd on that brown wire b/t the afm and circuit opening relay to cause that relay to pull in.

The afm only puts a gnd on that brown wire if the vane inside the afm moves aft approx 1/8" or more.

Kinda of a hard thing to figure out. Seems if one disconnected the afm plug........then disconnected the plug from the circuit opening relay............and then put a meter on ohms and checked the BROWN wire either at the circuit opening relay or the afms plug, he should find a open circuit or zero ohms on the meter. IF he finds say a half ohm or so on the meter someone has spliced into that brown wire with a gnd wire. Whos knows where or why.

I don't think it can be fixed from here not knowing what was changed.

I do know that I would do what I said. Ohm out the brown wire either at the afm or circuit opening relay with both elect plugs disconnected and see if you have a gnd on that wire or not. Should not have a gnd on that wire..............nor have any power on that wire when the key is put to ON and both those plugs disconnected.

That