ANd also how do I check if I am running lean or rich?

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BZ,

One more time...

On the OBDI ECMs, you can jump 'A' and 'B' terminals on the ALDL while the engine is running.

WARNING! This must be done after the engine is running. This is called Field Service Mode and will not harm the ECM.

If the ECM is in Open-Loop mode, the SES light will flash rapidly, about 2½ times per second. If it's in Closed-Loop mode, it will flash about once per second. When in Closed Loop mode, flashing less than once per second indicates the ECM is enriching the mixture above the 128 count base line. Flashing more than once per second indicates the ECM is leaning the mixture below the 128 base line.

A 10K or 3.9K resistor (don't remember which one) put between ALDL terminals 'A' and 'B' forces the ECM into Backup Fuel mode. This mode forces the ECM to use predetermined fuel calculations in the ECM PROM instead of the learned inputs in active RAM. This is commonly referred to as the "Limp Home" mode of operation.

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Later,
Vader
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"Make Me Bad"
Adobe Acrobat Reader 4.0

 

Which port is a and b

 

the 2 upper right ports are A & B

 

Vader...bzzzt...he has a carb, and CCCS does not flash out open/closed loop like EFI does. If he shorts A and B together while running all the SES will do is flash his error codes, or nothing at all if there aren't any. This is how you check for a true error code 12 (no dist. reference pulse) in CCCS cars (since it's running, there are dist. pulses. hehe)

BZ, you can check if your're running rich/lean by hooking a DIGITAL voltmeter to your O2 sensor. Jumper into the wire so you can leave it connected to the computer or else you're not helping anything. You must use a digital meter because analog meters will fry itdue top their lower resistance. If it reads above .45V you're rich, below, you're lean. You can tell if you are in clsed loop if you see it go back and forth between rich and lean.
...ed