Dying engine.

[mmerlinn]

New problem. 93 Aero 3.0L.

Engine dies every time I slow down.

But it ONLY happens once I have exceeded 10mph. Keep the speed under 10mph and it never dies.

Engine runs fine as long as I keep the revs up, like freeway speeds or city streets without stoplights or stop signs.

Every stop sign, every stoplight, requires a restart UNLESS I keep the revs up.

Any ideas what would cause the engine to shut down?

FWIW this does not appear to be a fuel issue. Delivered quantities of fuel and fuel pressures are within specs at all speeds.

Swapping control modules changes nothing.

 

[BrooklynBay]

Clean or replace the idle air control solenoid valve. Sometimes it could be a TCC solenoid issue but try the IAC valve first.

 

[mmerlinn]

Solved, but I have no clue what was causing the Aero to die.

Yesterday, I "drove" the Aero to a local wrecking yard, where I borrowed a spare control module that they had which gave me 3 modules to play with.

Plugged in the borrowed module. Drove around. Problem gone.
Plugged in a different spare module. Drove around. Problem gone.
Plugged in the ORIGINAL module. Drove around. Problem gone.
Cycled them REPEATEDLY for the next 2 hours. Problem stayed gone.

Finally, plugged the original back in and today am driving the Aero with NO dying issues.

All I can think of is either a bad connection or a wiring harness issue near the module since that is the only thing I monkeyed with. If the problem returns, I will closely examine the harness for problems.

 

[BrooklynBay]

Are you referring to the ignition module or the main computer module?

 

[mmerlinn]

Referring to the module located on the right fenderwell.

 

[BrooklynBay]

That's the ignition module.