DarylM

I have a 1982 Cavalier CL with 1.8L engine that has been in the family since 1983. Driven 72K miles since new. We now have a check engine light on, which our local repair shop is having difficulty diagnosing. Evidently, this must be one of the first vehicles having an OBD I system, as it has a single row receptacle in which to plug in a scan tool, rather than the normal two row receptacles. As the owner/mechanic doesn't have an adapter for such an unusual receptacle (is this the correct term?), he cannot read a fault code on any of his scan tools. Is there a way to "jump" any of the terminals on this receptacle block that will give a fault code by flashing the check engine light? We are stumped on this and could sure use some advice on this first of the Cavaliers. It's a nice car with full instrumentation, fancy wheel covers, velour upholstery, and upgraded suspension system. Thanks very much for any help you can offer.
DarylM

EinST

Welcome to the forum. Is it a 5-terminal ALDL connector? If so, try:

1. With key ON, engine OFF, jumper terminal D (test terminal) to terminal E (ground). Those are the rightmost two terminals.
2. Turn the ignition switch OFF.
3. The Service Engine Soon or Check Engine light should be flashing. If it isn't, turn the ignition OFF and remove the jumper wire. Turn the ignition ON and confirm that light is now on. If it is not, replace the bulb and try again. If the bulb still will not light, or if it does not flash with the test terminal grounded, the system should be diagnosed by an experienced driveability technician. If the light is OK, proceed as follows.
4. The code(s) stored in memory may be read either through counting the flashes of the dashboard warning lamp or through the use of a hand-held scan tool. If using the scan tool, connect it correctly to the ALDL.
5. After the terminals are connected, turn the ignition switch to the ON position, but DO NOT start the engine. The dash warning lamp should begin to flash Code 12. The code will display as one flash, a pause and two flashes. Code 12 is not a fault code. It is used as a system acknowledgment or handshake code; its presence indicates that the ECM can communicate as requested. Code 12 is used to begin every diagnostic sequence. Some vehicles also use Code 12 after all diagnostic codes have been sent.
6. After Code 12 has been transmitted 3 times, the fault codes, if any, will each be transmitted 3 times. The codes are stored and transmitted in numeric order from lowest to highest.

NOTE: The order of codes in the memory does not indicate the order of occurrence.

7. If there are no codes stored, but a driveability or emissions problem is evident, the system should be diagnosed by an experienced driveability technician.
8. If one or more codes are stored, record them.
9. Switch the ignition OFF and remove the jumper when finished with code retrieval.

kevinkpk

As always EinST is a real great help. I am attaching a link that might help a little with his post, this is also known as the "paperclip" method.How to Read Codes From Your Check Engine Light (For older cars)

DarylM

EinST and kevinkpk, thanks very much to you both! We're trying your tips tomorrow morning, and will report the findings to this forum in the next couple of days. The old Cavalier is so close to being road worthy once again, after being in storage for the past 10 years. A new carburetor really made a huge difference too. That carb is one complicated piece!

DarylM