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Topic: It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)... (Read 1404 times) previous topic - next topic

It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)...

Hello again!
It got colder here again and my '87 T-bird is having the same problems as last Autumn/Winter. It stalls sometimes or runs rough for a short wile, than it gets to normal.
I ran the self test and that's what I have:
KOEO: 31-31 and CM: 11-11.
To make sure I'm counting the flashes right here is a video I recorded while performing self test: http://www.americangranada.com/pics/engine_codes.wmv
What does the code 31 stand for? And how to slove that problem?
Thanks in advance for help!
Mariusz...

It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)...

Reply #1 –
I can't hear the engine, so I assume it's off.
I CAN hear the dog barking, though. :)

Code 31 is for the EGR system, often caused by a bad EGR position sensor (or its connections), or by built-up carbon holding the EGR valve partly open, making the computer think the sensor is out of range, and injecting exhaust gasses when it's not supposed to.

My Ford emissions book is for 88's, your 87 3.8 uses a different EGR system so I can't be specific with tests to run.
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)...

Reply #2 –
I've cleaned the EGR valve this year while changing the EGR valve gasket, so there shouldn't be any carbon build-up.
Guess it may be EGR position sensor, but would it cause engine to stall or run rough for a short while?

I was just wondering how to get KOER codes? Should I simply ground Self-Test IN and start the engine?
The description I have is for KOEO codes, so I'm not sure if KOER has the same procedure? Don't want to mess the computer... it takes up to two weeks to get something from USA here :D

KOER codes...

Reply #3 –
Finally I have the KOER codes too:
94 - Thermactor Air Injection system inoperative (left side)
44 - Thermactor Air Injection system inoperative (right side)
31 - PFE or EVP circuit below minimum voltage of 0.24 volts

I had disconnected the Air Pump for a few weeks last winter than I got a new pump and reinstalled it. Dunno why it says the Air Injection system is inoperative. Maybe the new pump is shot?

What should I do with code 31? How to get rid of all these failures?

It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)...

Reply #4 –
Guess I'm getting kinda boring but I have new codes. Thought I'll make a cold engine test here is KOEO codes on cold engine in the morning:
21 - ECT out of self test range 0.3 to 3.7 volts
24 - ACT sensor out of self test range 0.3 to 3.7 volts
I've no idea what ECT or ACT is...

It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)...

Reply #5 –
Quote
I've no idea what ECT or ACT is...
[COLOR="red"]E[/COLOR]ngine [COLOR="red"]C[/COLOR]oolant [COLOR="Red"]T[/COLOR]emperature
(Intake) [COLOR="red"]A[/COLOR]ir [COLOR="red"]C[/COLOR]harge [COLOR="red"]T[/COLOR]emperature
You did say it was a "cold" test, right?
Quote
Thermactor Air Injection system inoperative
Could be a bad pump, could be the valves or control solenoids that tell the valves to divert the air into the exhaust manifolds. Again, I haven't looked at 3.8s, but I assume they have the same type of system as a 5.0, with an air pipe that goes from the diverter valve to the back of the heads.
.
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

It got colder again and my 3.8 is stalling or running rough sometimes (KOEO codes)...

Reply #6 –
Quote from: MasterBlaster;113235
[COLOR="red"]E[/COLOR]ngine [COLOR="red"]C[/COLOR]oolant [COLOR="Red"]T[/COLOR]emperature
(Intake) [COLOR="red"]A[/COLOR]ir [COLOR="red"]C[/COLOR]harge [COLOR="red"]T[/COLOR]emperature
You did say it was a "cold" test, right?

Do you think that may be the reason why my T-bird has some running problems when it gets colder? When it's warmed up it's OK. It usually acts strange from time to time in the morning. Than it runs well all day long.
Quote

Could be a bad pump, could be the valves or control solenoids that tell the valves to divert the air into the exhaust manifolds. Again, I haven't looked at 3.8s, but I assume they have the same type of system as a 5.0, with an air pipe that goes from the diverter valve to the back of the heads.

Guess the Thermactor System isn't that important, is it?