Check Engine light - 84 automatic

[Donster]

OK, when we tried to set the timing on the 84, we jumpered the pins in the ADLD, but the Check Engine light didn't come on as it should have and I was told it's a bad ECM
Replaced the ECM tonight with a good one and also got a DKY1888 PROM in it. Drove the car over 35 mph to teach the ECM, but now when I accelerate, the CE light blinks??
 
Any idea what would cause that?
 
Won't throw any codes
 
\D

[Raydar]

Is the light blinking slowly? Quickly?
There are a couple scenarios.
One is that the ECM may be operating in some sort of a test routine. I don't really know how to access it. It's been a long time. (It may be pins A and B jumpered, with the engine running, and driving. I also may very well be wrong about this, however.)
Having said all that, one of the results of this "test mode" is that the Check Engine light will flash at different speeds, depending upon whether the exhaust is rich or lean. (Slow for lean, Fast for rich?)
I'll have to do some reading.

The other scenario is that the ECM is losing sight of the PROM. That will also cause the Check Engine light to flicker rapidly.
It should set a Code 51 if this happens, however.

I may have an 84 ECM. I'll try to remember to dig it out and bring it to the meeting.
It probably doesn't have a PROM in it, however.

[Donster]

blinks twice when accelerating, let of the gas, hit it again, blinks twice
 
First I thought it might be a short somewhere in the instrument pod, so I wiggled around but couldn't detect anything.
I also have a software program called L4 ScanConverter (See sample picture for V6 below) and a USB connector, which I connected to the ADLD. It reads everything correct, even tells me PROM IDs and such, but not telling me any error codes
 

 
\D

[Roger]

O2 sensor maybe?

[Donster]

I'm almost certain that the 02 sensor would throw a code, wouldn't it?
 
\D

[Roger]

I think there's a certain amount of time (seconds?) that an error must exist before it enters a code. Fierofool may be able to better answer this.
Because on the vacuum leak in my car, the CE light comes on for high idle but goes off soon afterwards and never sets a code.

Your's only comes on briefly when accelerating?

[Fierofool]

My experience with the O-2 is that it has to get pretty bad to set a code.  The 88 stalling problem finally manifested with a 45 code, I think it was.  Whatever it was, it indicated it was the O-2 sensor.  Prior to the code popping up, I couldn't identify the problem.  To set a code for idle speed, the speed has to be over or under the set point for a given period of time when the engine is at operating temp.  I don't know what the variance or time is. 

Don't know what the blinks twice thing is.  Don, you might try phonedawgz on PFF for that answer. 

[Raydar]

blinks twice when accelerating, let of the gas, hit it again, blinks twice
 
...but not telling me any error codes
 

 

Yes it is.
Look at the bottom left of the pic. "Trouble codes"
Code 22 - Low TPS voltage.
Code 34 - Low MAP sensor voltage.
You might have a bad 5V feed that is common to both of them.

You're getting two blinks. That might be that code flashing.
But that certainly doesn't explain why it's flashing without the A and B pins shorted. Odd.
(OTOH... I've heard that if a code is "happening" the light may flash. I didn't realize that it would flash the code, however. I may be totally off base, here. But even so, something isn't right.)

[Raydar]

Is that pic with the car driving? Sitting still?
Key on but engine off?
Lots of nonsensical sensor readings there.

[Donster]

Steve! I said the picture below is a sample! Look more closely and you'll see it's actually a screenshot from a V6! 
 
Was using it for demonstration only
 
\D

[Crash 86GT]

Sounds like a bad ground at the ADLA connector.

[Donster]

OK, I've looked for vacuum-leaks but couldn't find any.
Instead of shorting out/resetting the ECM, I installed a new (new to the car) one, which essentially should have the same affect.
Now when shorting/jumpering pin A & B, it won't even go into maintenance mode (error code 12)!

I checked all wires and ground and can't find anything wrong there.
Then I put in a 3rd (third!) ECM and it has the same issue!

However, I am using the same PROM on all of them, as I only have one automatic PROM, the DKY1888. Could a bad PROM be the issue?

As long as I can't get it to go into maintenance mode, it's useless to try and set the timing, which Shanine's car really does need, as it is running like a heap of dirt right now and sucking up lots and lots of gas, about 15 mpg!

Stumped!

\D

[Roger]

Engine NOT running...error Code 12 is correct.

That means your Diagnostive Mode is ACTIVE and the ECM is okay.

I'll stop by late tomorrow afternoon with a timing light if you need one.

[Donster]

Engine NOT running...error Code 12 is correct.

That means your Diagnostive Mode is ACTIVE and the ECM is okay.

I'll stop by late tomorrow afternoon with a timing light if you need one.

Roger -
Diagnostive Mode is NOT ACTIVE and the ECM is NOT okay.
It WON'T go into maintenance/diagnostic mode, that's what has got me stumped!

Anne and I just checked all wiring again, but can't find any issues

\D

[Roger]

Oops! Sorry, my mis-read.