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I bought a scan tool from Harbor Freight, you can also use a paper clip or jumper wire in the ALDL plug and then count the flashes from the “check” light on the dash….I’ve done both and the tool is easiest. There is also a device you can plug in the ALDL that reads to your phone, I’ve seen them on YouTube but don’t know anything about them.
It’s the access point for reading the “codes” stored in the cars computer, it’s located in the drivers side footwell just above the brake pedal. It’ll be attached to the carpet ABOVE your feet unless it’s been pulled loose previously. Go to YouTube and look for “ 90-95 C4 Corvette paper clip code reading” …or you can go to just about any of the major parts houses ( Auto Zone, O’Reillys ) and they’ll use a scan tool and you can see the codes.
the plug in or access point will look similar to this
What year C4 are you trying to pull the codes from? I ask because the process is not the same for all years. Some you can use the paper clip trick, some you cannot. Up to 93 the paper clip trick works. 94-95 requires compatible scan tool or laptop shareware and ALDL to usb cable. All C4’s except 96 are OBD1. 96 is OBD2 and requires compatible scan tool.
need to read to codes for a 96. Good to know info that it is OBD2 as I notice the code readers mention that. Thanks for the info. Having problems with the passenger side plugs. All showing very black. Have replaced them and still all are black. Car seems to run okay but not great.
Are the stock injectors are still in there? They have a reputation for sticking open. That would surely result in rich fuel mixture and black carbon deposits on the plugs.
I’m not saying to arbitrarily just replace them but I’d be at least checking them for faulty conditions.
