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Stalls at idle

731 Views 6 Replies 5 Participants Last post by  junkman
I have a 1983 280zx non-turbo, 5-speed. This morning it started and idled fine, I made one stop on the way to work, took it out of gear and engaged the emergency brakes and it shut off. It cranks fine but will not stay running below 1000rpm. It runs fine on the road at any speed, no problem. But when you slow down and the rpm's go below 1000, it shuts off. I have to turn the ignition switch all the way off and the back on before it will start. The fuel filter has been changed recently. Any suggestions? Maybe the coil? TPS?
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Post Edited (Oct 13, 10:06am)
It happens when I take it our of gear (neutral) or when I depress the clutch pedal and the speed drops below 1000rpm, namely idle speed.
Could be bad connection or sensor that controls fuel cut off.

Here is Wayne Monteath's great blurb:

The fuel pump control for the 82 - 83 N/A

For 82 - 83 N/A models the fuel pump starts and runs for ~ 5 seconds when the key is turned from "off" to "on" and then shuts the fuel pump "off" until the key is further turned to "start" at which time the fuel pump starts up again.

The ECU uses pin 13 to control the fuel pump operation since it does not have a FPCM. When the ignition switch is turned from "off" to "on" the main EFI relay closes and supplies battery voltage to pin 27 of the ECU. The ECU then supplies battery voltage to pin 13 of the ECU to close the Fuel Pump Relay for ~ 5 seconds. When the ignition switch is further advanced to the "start" position the "start" signal is sent to pin 26 of the ECU which in turn allows the ECU to provide battery voltage to pin 13 thus starting the fuel pump again.

The ECU also monitors the Ignition Coil Trigger on pin 18 coming from the '-' ignition coil terminal. If the engine stops / stalls or the engine speed drops below 50 RPM the ECU removes battery voltage from pin 13 which causes the Fuel Pump relay to open and stop the fuel pump.
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Thanks, I give that a look.
what about the fuel filter needing replacement?
change it cause it's cheap & easy or run a fuel pressure test to measure so you know.
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