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RX-7 2nd Gen Specific (1986-92) RX-7 1986-92 Discussion including performance modifications and technical support sections.

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Old 02-27-2009, 06:41 PM   #1
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Originally Posted by RoughRex View Post
Un-metered intake air is known to cause this issue. Make sure you have the Air Flow Meter (AFM) installed, connected, and is sitting level (it uses a flap to measure incoming air so if it's not level the flap may be affected by gravity and the reading may be off). Also check for major vacuum leaks. The car runs because the ECU ignores the AFM during startup but as soon as it switches from the "start" sequence to "run" the car dies because the AFM reading is too far off from what's actually making it into the intake.
Although you're right about the AFM function at startup, it doesn't seem to be the issue here.

(Correct me if I get any of this wrong)
I talked to him earlier and it runs for about a minute then shuts off. It idles at about 1500rpm roughly, and then no matter what (hitting the gas, not, etc.) it just dies after a while. Every vacuum leak I've ever had it's possible to keep the car running by hitting the gas (including when I left the BAC hose off so there was a HUGE amount of unmetered air going into the engine [granted it would only run at over 5k rpm, but it started and did run]).
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Old 02-27-2009, 09:35 PM   #2
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Originally Posted by My5ABaby View Post
Although you're right about the AFM function at startup, it doesn't seem to be the issue here.

(Correct me if I get any of this wrong)
I talked to him earlier and it runs for about a minute then shuts off. It idles at about 1500rpm roughly, and then no matter what (hitting the gas, not, etc.) it just dies after a while. Every vacuum leak I've ever had it's possible to keep the car running by hitting the gas (including when I left the BAC hose off so there was a HUGE amount of unmetered air going into the engine [granted it would only run at over 5k rpm, but it started and did run]).
AFM usually does cause that problem. I'm not sure if it's for a minute and a half though. Maybe at the most 30 seconds with Cold Start Assist still intact. I'd suggest setting the TPS as well as the bleed screw up top. Beyond that I would check the condition of the injectors, insuring that they're running correctly and firing and not seized.
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Old 02-28-2009, 01:17 PM   #3
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AFM usually does cause that problem. I'm not sure if it's for a minute and a half though. Maybe at the most 30 seconds with Cold Start Assist still intact. I'd suggest setting the TPS as well as the bleed screw up top. Beyond that I would check the condition of the injectors, insuring that they're running correctly and firing and not seized.
The AFM only comes into play after 500 rpm. As such, why would it run perfectly fine for about a minute and then die no matter what's going on? That doesn't indicate a vacuum leak to me. Granted, it would if you could keep it running after that point by keeping the idle up. However, in this case, (from the info I was given and my understanding of the issue), engine speed does not change the fact that it shuts off.

The injector thought could be plausible. It was in a field before he bought it and he's been working on getting the bad gas out. However, again, why does it shut off no matter what?

This is all based on the assumption that I understand the problem correct from a 5 minute phone call.
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