Electrical Car dosen't run without jumping the EEC IV test port
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If it has anything to do with gambling I have to wear a hat to cover up the capital L on my forehead
You'd have to depend on me and Noobz, in either case you're screw'd
Now, what kind'a BS...Oh look! A penny.
mine
you'd run out into traffic to grab a quarter
Oh look! A penny.
mine
I am going to send out the ECU to ECU Exchange. But in the meantime, I decided to open the ECU to see if I could see a burned trace. The inside of this ECU is very dark and difficult to see. However, I could see one that appears burned, but I'm not sure what it is too.
On the bright side, I tested the continuity on the other ECU and it checked out ok. I may go ahead and put it back in the car again to start the testing over.
On the bright side, I tested the continuity on the other ECU and it checked out ok. I may go ahead and put it back in the car again to start the testing over.
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Yes sir. That is definitely burned
Question is how? This is a 5-spd car right? Try one more thing before you send the ECU in. Plug it back in. Backprobe pin 46 to ground and turn the key to on. Do you measure any voltage?
The o2 harness jumper being configured wrong would cause this.
Really you want to check this to prevent burning up the ECU when it comes back repaired.
Question is how? This is a 5-spd car right? Try one more thing before you send the ECU in. Plug it back in. Backprobe pin 46 to ground and turn the key to on. Do you measure any voltage?
The o2 harness jumper being configured wrong would cause this.
Really you want to check this to prevent burning up the ECU when it comes back repaired.
Also, you have another trace that is burned as well. This one is pin 46. I’d need to poke around a bit to see what the other trace is for.
This ECU has issues
This ECU has issues
Yes sir, 5 speed car. I had read somewhere about burning a trace in the ECU due to an improperly pinned O2 harness.
I will try that... but just so I'm clear, I will put the ECU back in and then ground pin 46? Or test pin 46 for voltage at the ECU? I apologize. I'm not sure what you mean by backprobe pin 46.
Thank you!
I will try that... but just so I'm clear, I will put the ECU back in and then ground pin 46? Or test pin 46 for voltage at the ECU? I apologize. I'm not sure what you mean by backprobe pin 46.
Thank you!
Put ECU in, with it plugged in, you stick the probe from the meter into the connector on the backside to make contact with the pin 46 wire. Thats backprobing
Set the meter to voltage. Turn the key to on and see what you get. Should be 0 or very close to 0.
Another way is to just locate the o2 sensor harness under the MaF and take a pic of the jumper location.
A 90 5-spd should match top left
Set the meter to voltage. Turn the key to on and see what you get. Should be 0 or very close to 0.
Another way is to just locate the o2 sensor harness under the MaF and take a pic of the jumper location.
A 90 5-spd should match top left
Good evening all!
So I took a look at the O2 sensor harness and it looked like it was pinned properly for a 88-90, 5 spd. Just for safety sake, with the ECU plugged in, I checked the voltage on pin 46. To my surprise, when I turned on the key I got .04 volts. It jumped to .05v when I cranked the engine.
Knowing there wasn't much current on pin 46, I decided to pull out the A9L and put my A3M back in and test with it. It also had .04v at pin 46 with the key on. However, this time I heard the fuel pump charge without the signal wire and CEL wire twisted together at the EEC DLC.
So... I tried starting it and it fired right up. Though it seems to be running very rich (the idle is slightly lopey because of it). But at least there is headway... though I'm not sure why because I just tried this ECU last week and it wouldn't charge the fuel pump.
Question... the A3M is out of a '93. Would that be an issue running it in this 1990 car?
Thank you again everyone!
So I took a look at the O2 sensor harness and it looked like it was pinned properly for a 88-90, 5 spd. Just for safety sake, with the ECU plugged in, I checked the voltage on pin 46. To my surprise, when I turned on the key I got .04 volts. It jumped to .05v when I cranked the engine.
Knowing there wasn't much current on pin 46, I decided to pull out the A9L and put my A3M back in and test with it. It also had .04v at pin 46 with the key on. However, this time I heard the fuel pump charge without the signal wire and CEL wire twisted together at the EEC DLC.
So... I tried starting it and it fired right up. Though it seems to be running very rich (the idle is slightly lopey because of it). But at least there is headway... though I'm not sure why because I just tried this ECU last week and it wouldn't charge the fuel pump.
Question... the A3M is out of a '93. Would that be an issue running it in this 1990 car?
Thank you again everyone!
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A3M and A9L are both manual ECU's and pretty close to identical. Shouldn't be any issue.
Do you have the two wires disconnected at the test port (other than the teo fuel pump wires that need to be) torun with that ECU connected? They def need to be separated as that is not a normal connection
Do you have the two wires disconnected at the test port (other than the teo fuel pump wires that need to be) torun with that ECU connected? They def need to be separated as that is not a normal connection
Too easy.
All you have to do is 'point an shoot' then 'hurry up an wait'. It does beat digging through buckets of greasy, 30 yr old wiring harnesses.
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The A3m is a convertible ECU. Back in the " old days " people thought they made more power because of the added weight in the car. Something about the tuning from FORD. It's probably not true but still an old myth of mustang fanatics. Just like the ssp cop cars made more power because of special computer tuning by ford. To my knowledge they used the same computers and strategy as every other LX 5.0.
There were some subtle differences. The A9T (for the SSP cars) was rich-tuned when in closed loop, but would run a little leaner at WOT. They also got a little bit more spark advance and a little extra EGR flow.
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